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Discussion Starter · #1 ·
Ok I have a question to ask and some advice to seek. It may take an expert to solve this one.

2000 Ford Taurus SE Sedan. OHV Overhead Valve engine. (Not Overhead Cam)
Cam in block with pushrods.
aka: the 3.0 L V6 Vulcan engine. (Not the Duratech engine)


Due to original engine failure after 285,000 km ( Cam bearings wore out badly due to head gasket leak, coolant leak into engine in valley area. this led to camshaft going badly out of alignment and chewing up the Cam sync gear, leading to oil pump drive failure, and no oil pressure therefore. Engine was then dead in the water / on the road) , i finally got around to installing a good used engine of the exact same type, engine ...from same year and model, exact same engine.

It took time, was not easy, but i did it myself in home garage, over the past 2 years or so.

Working on this car is NOT easy. Packed in pretty tight. Complex & difficult .

I digress.

It is all back together, and looking good, with a good used engine.

First attempts to turn it over and try to start it, after 2 years sitting in garage.
It did turn over and attempted to fire ... but then went into, I think, "PATS" mode, and no key will CRANK it now.

I have a NO CRANK situation, with all three previous chip keys.

I have confirmed all the starter system is good, because if I bypass the PCM lockout, by providing GROUND to the
starter relay ... it cranks all fine.

But I assume if there is a problem with the Computer / PCM, locking out the vehicle from starting, then it probably will not provide spark or fuel injection signal, and will probably not run the fuel pump.

THEFT red warning flashes every 2 seconds, and still does constantly when the key is left in the RUN position for 10, 20, or even 30 min. It does not clear out and go solid or go away.

I am guessing the car has locked itself in Alarm mode / PATS lockout, or maybe a problem with the PCM, or maybe in the 2 yrs that the battery has been out of the car ... it may have lost the programming of ALL the 3 keys.

I am not totally sure.

Funny thing ... I tried to hook up my Forscan OBD 2 reader to the OBD 2 port, to look for codes, but can't seem to connect to computer. that is really funny.

It's a long difficult project, replacing that engine at home ... and I wanna try and see if I can fire up this engine.

It's all looking good ... just gotta figure this out.

I have service manual on CD, have researched this. Have looked online as well, and tried to leave key in Run position for 10 min or so, as suggested in one online help video ... but does not clear the THEFT flashing PATS warning.

One suggestion is that the car has lost / forgotten all the keys, and the keys have to be re-programmed into the PCM.

I was wondering if I have locked the perimeter alarm system, cause I had the HOOD OFF before, and the car actually looks for forced doors, trunk lid , and hood .... ya. But now I have put the HOOD back on and closed it, and re tried, but nope ... the NO CRANK and flashing THEFT red led on the dash persists.

Manuals and Service Manual on CD, suggest "Take car to Dealer and have them look at it."

Any simple way to CLEAR a PATS lockout ? Passive any theft system Lockout. (THEFT light flashing every 2 seconds always .... even after key left in RUN position on ignition for long time ... )

Any simple way to CLEAR a Perimeter Alarm lockout on this car ?

( I think I have tried the usual ways I have discovered ... but no luck )

What advice or info could any expert give me on this "NO CRANK / NO Start" situation.

[ Manuals also suggest Bad PCM or bad connections .... but I don't think so. Everything else seems to be
working fine. Remote locks and unlocks car, and most else behaves normally, seeming to indicate to me
that the PCM is working and responding correctly. ]

This may be a complex one to solve ...

Thanks in advance for any advice or help.

I would like to bring this old baby back to life ... after a long personal project ... and much personal work and effort.

All the rest of the car is good / in good shape. I like it and wanna put it on the road again before winter here in Canada.

Thanks.
 

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So to be clear:
  • You replaced the engine and kept the PCM and the complete wiring.
  • When you turn the key to Run:
    • The THEFT light keeps on blinking every 2 seconds.
    • You do not hear the fuel pump in the back engage for a few seconds.
    • The OBD adapter does not connect to the PCM (note the ignition must be in Run for that).
Since the very first time the engine actually did turn over, the PCM must have worked and have recognized the key. Perhaps you can carefully check the ground strap of the PCM.

You could also check fuse 23 (Air Bag Module and PATS Transceiver) underneath the dash.

As far as I know, there is no such thing as a "PATS lockout" (a key is recognized or it is not).

Note that the locking and unlocking of the doors (among other things) is done by the GEM (General Electronic Module) underneath the dash. It does not prove the PCM is working.
 

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Discussion Starter · #4 ·
Reply to Architect:

Thank you.

Yes: Replaced engine, and used original wiring harness and original PCM that was in the car originally, and was all working before at that time. Engine replaced due to an internal mechanical engine failure. All working good up till that mechanical failure.

Fuel pump. Yes, hear it run for just an instant, but not always. I would say funny behaviour right now. ( unclear though, makes a moan or groan, then stops. I am familiar with the sound it made when car was working all find before the engine change... and could be suspect. A fuel pressure check might be in order. )

Yes. OBD connector - cannot seem to connect to connect to the computer to view any possible codes. Strange. Have connected before engine change ... worked before. looked at codes before and cleared and fixed stuff based on codes. This itself suggests a problem with the PCM ... because manuals say: " PATS will never lock out the OBD port. " ( ie you should always be able to connect to the PCM ... unless something is wrong with it / or the OBD port or wiring )

Ground Strap of PCM ... yes I should check that - thanks.

PATS lockout - thanks. I see your point. By that term I mean, it is behaving like it is not recognizing any of the 3 keys that were previously working. This could be a bad PCM. ( The PCM should NEVER normally lose memory of the Keys, even if the battery is disconnected for 2 years ... i am thinking ... but one never knows for sure with computers and electronics. any think is possible i would also assume. But read later down, i will explain what one "experienced" / practical person told me about fords and their anti-theft systems. Real practical advice from someone who's dealt with ford trucks etc. seen this sort of thing happen)

Fuse 23 - yes I checked two fuses related to this. I think fuse 23 and 9 or 5. I will go over that. thanks.

Thanks for letting me know the unlocking of the doors, with the remote, is not related to the PCM.


Reply to Automender12345 :

Wrecker told me engine was from same year of car. Came out of a 2000 Ford Taurus. Is virtually exact to the original.

And yes, best of my knowledge, all connectors are re connected correctly. (Except for a few A/C Air conditioner system connectors, because I removed all the AC system from the car including the compressor, and installed the shorter serpentine belt. Car worked fine before with those AC connectors off, no engine lights and no codes related to that. )

Wiring Harness is from original car. Just flopped back over and reconnected to everything again on the used engine, all sensors and connectors and fuel injectors etc, and to the PCM again.



Next Post will explain some furthur research and questions I asked some other persons.
 

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Discussion Starter · #5 ·
Furthur research since my original / first post:

I went into the 2000 Taurus service manual on CD, and read some more and printed schematics and pin outs and location drawings for a few connectors related to the Starter System relay wiring. The part of the circuit that provides ground to the starter relay in the Fuse Box beside the battery in the engine compartment. It shows a pink wire, leading from pin 86 (from memory) of the starter relay, through another connector on the driver's side fender of the car, then over to the PCM connector, pin 44 i think from memory. It says to check the resistance of this path, and if greater than five (5) ohms ... "fix the circuit".

So ya ... I gotta check that part of the circuit and see if there is any problem there.


I spoke with one mechanic who advises: "Those Fords have a system that if the keys are not recognized and you gotta re program the PCM ... only a Dealer Can do that. You are off to the Dealership."

I spoke with another person, who works for a different Mechanic, who has past experience with Ford Trucks who advises:

" Ya, we used to see that sort of thing a lot with our Ford pickup trucks. And we would do the following:
1. Make sure the Battery is good, and charged and reading at least 12 volts
2. Disconnect the Battery terminals and touch the two battery clamps together to make sure the system in the car is
discharged down to zero volts.
3. Put the ignition key in the ignition, and turn it to the run position. (Before reconnecting the Battery.)
4. Reconnect the Battery, leaving the key in, and in the RUN position, and let it sit like that for awhile, see if on repowering, it recognizes the key. "

" that would work for us, many times on those FORD (pickup) Trucks"

This makes some sense to try to me.
My battery was originally low when I re-installed it. Maybe 10 Volts.
I put the battery charger on it, after, overnight, then re-tried next day. Voltage up then.

This is similar to another procedure I read online. Minus the touch terminals together to discharge system to zero volts.

This makes sense electrically and with computers / PCM's . Trying to do a re-set.

thanks all... gotta go. will report back whatever happens. Advice much appreciated. Working on it ....
 

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Fuel pump. Yes, hear it run for just an instant, but not always. I would say funny behaviour right now. ( unclear though, makes a moan or groan, then stops. I am familiar with the sound it made when car was working all find before the engine change... and could be suspect. A fuel pressure check might be in order. )
This seems OK. It indeed moans and groans for 2 seconds. This also shows that the PATS is recognizing your key. If it doesn't, the PCM will refuse to start the engine, and will not bother powering the fuel pump either.
I went into the 2000 Taurus service manual on CD, and read some more and printed schematics and pin outs and location drawings for a few connectors related to the Starter System relay wiring. The part of the circuit that provides ground to the starter relay in the Fuse Box beside the battery in the engine compartment. It shows a pink wire, leading from pin 86 (from memory) of the starter relay, through another connector on the driver's side fender of the car, then over to the PCM connector, pin 44 i think from memory. It says to check the resistance of this path, and if greater than five (5) ohms ... "fix the circuit".
Yes, that is correct. The schematic (from paper version of the 2000 Wiring Diagrams):
Font Schematic Rectangle Parallel Book

The PCM will only start the engine if the transmission is in P or N. The Transmission Range Sensor (TRS, a.k.a. Neutral Safety Switch or NSS) only powers the Starter Relay (in the schematic called K22, but it is relay 23 in the engine compartment) when the ignition is in Start and the Transmission in P or N. Relay 37 under the dash should of course be fine.
This is the wiring of the TRS:
Font Schematic Parallel Engineering Pattern

Through pin 6 of its connector it also informs the PCM (pin 50) that the transmission is in P or N. Without it, the PCM will not even try to pull the other side of the Starter Relay to the ground.

So, you could:
  • Pull the 12 pin connector from the TRS, push it back in and try to start the engine again.
  • Check the Starter Relay (#23 in the engine compartment) by interchanging it with the one next to it (#24: Low Speed Fan Relay) and try again.
  • Pull out the Starter Relay alltogether.
  • Connect the terminal where pin 30 of the relay would go to the battery positive. The starter should run immediately, even without the key in the ignition. Beware that there is no safety at this level and the car will happily run you over if the transmission is not in P or N.
  • Put a 12V test light between the terminal where pin 85 of the relay would go and the ground (or battery negative).
    • When you try to start the engine, the test light should light up indicating the TRS agrees that the transmission is in P or N and powers the relay.
  • Put the 12V test light between the battery positive and the terminal where pin 86 of the relay would go.
    • When you try to start the engine, the PCM should pull pin 86 to the ground and it should light up again, indicating the PCM also understands the transmission is in P or N and that a valid key was recognized.
 

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Now that I think about it again: it is very strange the OBD monitor does not connect. So one question: when you hear the fuel pump "moan and groan" in the back for 2 seconds, the THEFT light in the instrument panel is out, right? Just to rule out that my statement "fuel pump runs, so key is recognized" is in fact wrong and that it indeed could be the PCM.
 

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Maybe you have to check the connectivity of each wire from the OBD plug to the PCM. Also have you been able to connect the monitor before. I seem to remember that I had issues connecting the Forscan to my Taurus. I was thinking that the car had to be running in order to connect.
Seems like a great idea to check that the transmission is indicating it is in neutral. Also is the starter solenoid clicking or absolutely no sound at all?
 

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Discussion Starter · #9 ·
Reply to Architech post #7 :

Red THEFT light on the dash continues to flash every 2 seconds all the time and never stops (No it does not go out).
And yes, I agree that it is possible that it could be a defective PCM / Computer.

And thank you for the other schematics & advice / troubleshooting tips in Post #6. I will print off & include in my troubleshooting / testing. thanks. very detailed & good info. much appreciated.


Reply to Automender12345 Post #8 :

Yes, a flakey OBD plug or wiring is one of the possibilities why I can't connect Forscan to see codes etc.
Yes, in the past, I connected to the car's computer with this laptop & setup, could see & read codes etc.
Car's engine did not have to be running ... but key had to be in the ON or Run position...

The functional parts of the car's starter system all seem to be working. Relays, main wiring, starter motor.
The car will turn over / crank normally ... if I just bypass the part where the PCM denies Ground to the starter relay.
i.e. I give ground to pin 86 of starter relay, with a jumper wire. Starter relay K22. C1017 Pin 86 in top schematic image Architech posted in post #6
 

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Discussion Starter · #10 ·
I did not have much time to do any real troubleshooting since last posts. Busy with work & other stuff & caught cold / sick / not online often.

I did some quick tests to check grounds to PCM & car body & engine. They seem good. very low resistance.

Other things in life / various numerous issues keeping me quite busy. But I will get to this as well .

Thanks for all advice & help ... much appreciated.

P.S. oh ya... yes, as suggested, it is a standard thing to do, that if you are having these sorts of issues, to try and
"RE SEAT Connectors" ie. Pull PCM connector, inspect it, try to re-connect it. sometimes a pin is not making connection. same with other key connectors in the system path(s). ? TRS connector ? Others ?

try to: RE SEAT CONNECTORs !
 

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I assumed that the PCM is either working, or it is not. But that is not true. It uses way too much power and will drain the battery if it would be fully on all the time. See this schematic:
Schematic Font Rectangle Material property Handwriting

The PCM gets (pin 55) its Keep Alive power. It will probably keep the PCM in a kind of sleep mode (doing things like blinking the THEFT light). It only really powers on if it receives power on pin 71. So you also need to check fuse #2 in the engine compartment, fuse #25 underneath the dash and relay #31 in the engine compartment (this is what K163 is), for example by interchanging it with relay #33 next to it (A/C clutch).
 

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Discussion Starter · #12 ·
OK, so you are suggesting the PCM is not fully powered up for some reason, but fooling me by remaining in Sleep mode.

So, if PCM is not fully powered up, obviously it cannot check keys, or do anything else it needs to do to attempt to start the car. Thanks for informing me of this possibility as well. Will check / keep that in mind.



[ Progress: have printed & analysed the schematics and pin outs / drawings for connectors for the TRS - Transmission Range Sensor - circuit to the PCM. planning a few simple electrical tests with meter to see if that system is working ok. Yes, Ford has certainly included a couple of "parallel" systems to ensure you are in Park or Neutral ... before anything will attempt to start this car. But this also leads to more complexity and possible failure points / trouble points ... both the starter circuit, and the PCM are locked out if not in P or N, and of course any of these two circuits, connectors, wires, and TRS switch components could fail anywhere along their path. A mechanic's nightmare.]
 

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Seems like a similar issue to what I'm having with my 2000. My car will start most of the time, but then...it doesn't. No crank, no start, flashing PATS light. Before it started throwing codes I was able to crank it at least, but the fuel pump wouldn't run and the car wouldn't start. Or it would start and then die. And this just started a few days after doing a bunch of engine work after a failed valve spring. Seems like disturbing of the harness may be related in both of our cases.

At least in my case I have communication with the PCM, and I was able to retrieve codes. The big red flag that I got in my case was B1342, which in my FSM is listed as EEPROM failure/corruption which means the PCM needs to be replaced. The fact you can't communicate and pull codes (you need the key to be fully on but it should still work) means it may have died on you. Maybe they built in a timer at the factory to where these just die after 22-23 years of existence, lol. However, looking into my issue means I've found a lot of useful information on this topic, so let's start with some basics.

Have you verified that the PCM power relay is activating with the key on? That's the first step given no communication. It's easy to swap with a non critical relay for testing purposes. When you initially turn the key to run, the THEFT light should go solid for about 3 seconds, and then go out if the PCM is happy with the key's validity. IF you're getting an actual PATS error, the light should flash rapidly or stay on solid depending on the error it's generating. If it never stops flashing at the normal rate that it does when the key is turned to "off", then it may not be energizing and actually booting up.

You also want to check to make sure the grounding bolt (G103) above the PCM casing is connected properly as well and not badly corroded or otherwise in distress.
 

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Discussion Starter · #14 ·
Reply to ice445 :

Thanks. Well as of last night, I did a few tests. I can say YES, I believe the PCM relay is activating when the Key is ON.

Yes, you are correct, it is possible the PCM died on me. But I have to exhaust / do a few other tests to see if it is not something else first. You are correct: if I have no communication / can not connect through the OBD port, that is not a good sign for the PCM.

The lugs and ground strap were taken off the Ground bolt near the PCM connector, and polished up and cleaned for good connection. The resistance to ground measured with a digital volt meter, and very low, like 0.1 ohm, so that is indicating a good ground there.


Update to all:

So I removed and inspected PCM relay. Was pretty clean, but I polished up contact tangs & sprayed with contact cleaner & wiped clean & re-inserted with a wire tap out from contact 5 which should be the output to supply power to the PCM according to schematic I printed off from service manual.
Connected DC voltmeter to tap wire. Key off - zero volts. Key ON - 12 volts. So that looks good at that point.
PCM relay is working and supplying 12 power to PCM wire. All else that actuates the relay seems working and therefore should be good.
[ From car's glove box manual, pgs 138 139 140 - that is fuse/relay location 31 "PCM Power Relay", a little black square with 5 tangs that plug in, over on the far right side of the Fuse box beside the Battery ]
[ From Schematic this is K163 PCM power relay, pin 5 ]

Next test was to remove the main fuse supplying power to the PCM and check it out.
Looked good. Not burned out. Zero resistance across it's tangs. Tangs polished up and contact cleaned.
[ large green translucent plastic plug in fuse, 30 A ]
[ from Car's Manual: Fuse location 2, 30 A, PCM Fuse, over on the left side of fuse box]
[ from schematic: F102 30 A at the top of the page ]

So then I pull the fuse, and insert a DC Amp Meter, set in the high range, 10A full scale, in the fuse's place.
Key OFF - zero Amps measured.
Key ON - 2.05 Amps measured.

So by this test, I see that the PCM power circuit is at least drawing 2.05 Amps through it.
I don't know if this is in the "good range" / within spec. But at least I can see the PCM is drawing
a signifigant amount of current, with KEY ON and seems like that circuit is intact, likely good, and drawing
power for the PCM.

Would 2.05 Amps seem like enough power, for a PCM at rest ? Does that seem "within spec" ?

More tests to come ... as I have time.

The next tests will likely be for the TRS - Transmission Range Sensor - circuits / wiring / connectors in between.
Will likely involve some resistance measurements between some pins on the PCM connector.

Then a pin on the PCM connector to the Starter Relay. the cct that provides the ground to the starter relay.
To see if that circuit is good / seems good.

Looking at it last night, I don't think I ever removed or touched the connector on the TRS Transmission Range Sensor,
during any of my work to put the used engine in. Or never ever in the life of the car. So that's never been "disturbed".
Transmission remained in the car, for the used engine install .

I'd like to see later if I can scan and post images of schematics & drawings I pulled out of the 2000 Taurus Service Manual on CD. Good reference material. Previous posts showed images of some of them.

The ideas others are giving me here are helping shape my troubleshooting.

Thanks.
 

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The fact you can't communicate and pull codes (you need the key to be fully on but it should still work) means it may have died on you.
Agree. This really sounds like a bad PCM. There is definitely power on the PCM (pin 71 of the PCM and pin 5 of the relay) and it even draws 2 A. Yet the OBDII monitor does not connect. And the key is not recognized (THEFT light keeps blinking).

I'd say that checking of the TRS or any of the fuses is not needed. The PCM is dead.
 

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Discussion Starter · #16 ·
Poor Grounds.

Deteriorated / corroded just enough to cause a PCM issue. Not providing full voltage or current return sufficient to run the PCM correctly.

I unbolted the various ground lugs / studs and re-did / cleaned them all up and soldered the Grounds, and now
the PCM is working / behaving correctly. All 3 keys are recognized now, Car will CRANK normally now, and THEFT light goes off indicating PATS - Passive Anti Theft System - is off and passing key the checks.

Each ground LUG was unbolted, lug polished with wire wheel, both sides, and paint on body steel where lug clamps to scraped down to bare metal (by a hand file). A small file was used on each LUG, after the crimp, where the wire ends, to get down to the bare metal of the lug (past the zinc coating), and the end of the wire spot soldered, with larger soldering iron, to the lug for SURE connection. (these ground lugs are only crimped for a mechanical connection only, not soldered. So with time, corrosion gets between the crimp and the wire and degrades the connection.)

I added A separate wire, dedicated ground to PCM, about 6ft long, 12GA,from the Negative battery terminal (black wire) to body ground lug near the battery direct to the PCM ground stud near the PCM connector on the Firewall.

I figured: Why should something as important as the car's PCM ...depend on a ground through the car's body metal, or through the engine block / braided ground strap ? The PCM should have it's own dedicated ground wire direct as possible from Battery Negative black cable. So I added one. Ran a 6 ft piece of wire w/soldered lugs around the edge of engine compartment and along back firewall and straight to PCM ground nut near PCM connector on firewall.
( added: from battery body ground nut near battery, direct to PCM ground stud on firewall near PCM connector)

Braided Ground Strap from PCM stud to engine: Looks RATTY. I soldered it too / wire ends to lugs & re-installed.
I should just get a new one and replace it. Braided flat cable is starting to degrade near where it is crimped to the lug.

PCM cable has a double black small wire to PCM ground stud on firewall - soldered wire end to lug & re-connected / bolted down again.

There is also a 2nd ground stud to body, near the Battery, disconnected / cleaned up, soldered wire end to lug, cleaned body metal (removed paint) where attaches, and bolted those 2 wire lugs down again.

PCM should have it's own dedicated ground wire to battery negative post or cable. As direct as possible, in addition to
ground from body or from engine strap. I added that. There's one for FORD to think about.

Why should something as important as a PCM, which basically runs the whole vehicle, depend on a ground through the body? or through the engine Block?


PCM seems good. Car Cranks now, normally, all 3 keys, but still not starting. Trying ... but no full start yet.

I figure fuel left from 2 years ago in tank / quarter tank in it - is a bit old and stale.
I purged a few litres through the system through the schrader (bike valve) on the fuel rail, into a container,
when the pump runs on startup ... but still no luck.

May have to empty the tank somehow and put fresh fuel in it. 2 year old fuel / stabilizer added / but probably does not help.

After a few crank attempts, the smell of partially combusted fuel coming out tail pipe, and engine stutters / tries to fire, but not very well.

I connected Forscan / OBD II reader sucessfully now, and have codes but only "GEM low voltage" code.
and PCM low voltage code - likely from before.

Engine is used too - and sat on warehouse shelf all that time as well - from around 2000 ... so who knows...
injectors may not all be working.

Troubleshooting continues ... but at least now I know it is recognizing keys and Cranking normally. Probably providing the signals for spark & fuel injection. Fuel Pump is priming on startup more normally now.

It will take a little time ... but I WILL get this engine running.

GETTING CLOSER.

P.S. RE-Measured again PCM current draw thru 30 A PCM fuse w/ DC Amp meter with grounds fixed.
Key ON - measure now: 2.67 Amps draw initially, then down to 1.67 Amps steady state after that, engine not running. ( a little different than the 2.05 Amps i measured before, with the poor grounds and PCM not responding / no crank / no keys recognized )


So Conclusion: Funny PCM behaviour / and NO CRANK / No Keys recognized - can indeed be POOR GROUND connections ... even if you measure a low low resistance on grounds, with a digital voltmeter. It must be that the poor grounds give a very poor current carrying capacity ... and the PCM won't work properly.

You have to have VERY GOOD / Solid GROUNDS. Don't assume they're good, even if tested w/meter.

Pull them apart and look at them and just RE-Do them and Solder them (wire to lug) / and clean them up, and clean the body metal where they are supposed to press down on. Remove the paint on the body metal down to bare metal.
Maybe add contact grease / dielectric compound where the lugs screw down.

Consider adding a separate direct ground wire to the PCM ground lug.

Replace that crappy flat braided strap if old and corroded / crappy.
 

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Bulls have a weak grounding system. Pic of my first issue of several, this was causing bad idle speed. I sanded the surface, then used anti-corrosion compound on the steel and threads, and all was good. I was chasing idle position not steady and spend too much time tracing why the signal return did not match the body volts. Since all mine have this cleaned and treated as a routine one time fix.
Also add a ground cable to fender secondary ground, eyelet under the clamp bolt and to the mid fender ground bolt. And cleanup the OE cable to fender surface.
All 3 of my G-4's have this done.
-chart-
 

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Discussion Starter · #18 ·
Reply to Chartmaker: Ya ... no kidding. Thanks.


I plan to tie in that 2nd Body ground nut near the battery to my added 6 ft Ground Cable.

So basically: connect / tie all the body ground bolts all together with an ADDED copper wire soldered to new LUGS, of large enough size, that travels around the edge of the engine compartment and along the back firewall at the top / back.

A new braided strap to the passenger side of engine.

Maybe another / second / redundant heavy guage cable / ground - to the Driver's side of engine as well
(There's a free threaded hole on the side of the engine head on the Driver's side)
(So this would be in addition to the "stock" large ground cable that goes to the Transmission bolt bottom front of Engine)

[ Now I will search how to possibly empty old fuel from tank, using car's own pump ... make pump run and open up fuel hose somehow into a Gas Can. ]

thanks everyone. I will post progress. Interesting issues ....
 

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Discussion Starter · #19 ·
Printed Schematics, location drawings, and connector pin outs, from service manual, related to Fuel Pump system. Studying to determine how to empty the remaining quarter tank of 2 yr old fuel, by running pump and pump the fuel out of the car, into a gas can.

Haynes manual suggests the PCM provides ground to Fuel Pump Relay in fuse box beside battery to run the pump.
Says: PCM runs pump, when PCM sees electrical pulses from the Cam Synch. ie. when the engine is running / turning.
Will try that.

But study of schematics also shows a Fuel Pump / System Module near the back of the car, through which power and ground are provided to the fuel pump, and also with control signals / wires going back to the PCM.

Also shown is an Inertial Shut off switch with manual Reset button. ( shuts off fuel pump if it senses a collision / impact ).

Looking also for convenient spot / or Connector, if necessary, near the pump, to hot wire power to the pump directly.
Looking under car, I have found a connector on the front right corner of the tank, accessible underneath, and looks like the wires are the correct colours, per the schematics, to disconnect, gain access, and hot wire / provide power directly to run the pump.

A hose in the engine bay, from the fuel supply, fuel rail connection, would go then, to a gas can. Run pump remotely. Empty tank. ... In theory .

Investigating.
 

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Printed Schematics, location drawings, and connector pin outs, from service manual, related to Fuel Pump system. Studying to determine how to empty the remaining quarter tank of 2 yr old fuel, by running pump and pump the fuel out of the car, into a gas can.

Haynes manual suggests the PCM provides ground to Fuel Pump Relay in fuse box beside battery to run the pump.
Says: PCM runs pump, when PCM sees electrical pulses from the Cam Synch. ie. when the engine is running / turning.
Will try that.

But study of schematics also shows a Fuel Pump / System Module near the back of the car, through which power and ground are provided to the fuel pump, and also with control signals / wires going back to the PCM.

Also shown is an Inertial Shut off switch with manual Reset button. ( shuts off fuel pump if it senses a collision / impact ).

Looking also for convenient spot / or Connector, if necessary, near the pump, to hot wire power to the pump directly.
Looking under car, I have found a connector on the front right corner of the tank, accessible underneath, and looks like the wires are the correct colours, per the schematics, to disconnect, gain access, and hot wire / provide power directly to run the pump.

A hose in the engine bay, from the fuel supply, fuel rail connection, would go then, to a gas can. Run pump remotely. Empty tank. ... In theory .

Investigating.
I removed the fuel filter outlet connection, Then put a hose over the outlet nipple of the filter and other end of the hose into a fuel tank I use for the lawn mowers.
Hot wired at the inertia switch. Used a lawn mower battery as a source.
-chart-
 
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