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Discussion Starter · #1 · (Edited)
I put a 98+ vulcan motor in my 97 that had a vulcan in it. The trans is an AX4N. Now the car is throwing p0707 and p0743 codes. Haven't had a chance to drive it, as I have been tracking down codes and making the 98 harness work with the 97 computer (cam sensor and stuff).

The sensor on the passenger side back of the trans (shares harness with crank sensor) had a different plug on it than on the trans. Cut off the plug from the 97 and wired it onto the 98 harness and plugged it in. The p0743 code went away for awhile, but is back now.

I am unsure what else to look for. The trans had no issues with the old motor.

I need someone with some solid suggestions and knowledge of the possible differences in the wiring, and how to trace those down.

Thanks!
 

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Boostforfun, use the search feature at the top of this page and search: Engine Swap Problems by Jim Howard. After that, might search: engine wiring harness problems. Good luck.
 

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Discussion Starter · #4 ·
That didn't really help. That post is discussing more the differences between the transmissions of varying years. My car has the 97 PCM, the 97 trans, and this setup worked great in my car previously.

The only question I have is how to make the 98+ engine harness control the 97 trans. I am pulling the 2 codes listed above, and that is it.
 

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Dont know about the po707 trs code (only that number of pins can differ), but the tcc solenoid (po743) is different 98+ and not interchangeable electrically.
 

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Discussion Starter · #6 ·
yeah, i read those exact words elsewhere.

that isn't my problem. I have the 97 TCC. It will talk to my ECU or PCM just fine. I just need to figure how to adapt the wiring to make sure they are speaking on the same channel...

This is the same type of problem I was having with my cam position sensor. Everyone told me they weren't interchangable, which is true. But all I had to do was find out that both communicated through pin 85 to the ECU, and then adapt the wiring. The cam sensor works fine now with no code.
 

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I Feel your pain. I put a 96 Vulcan into a 97 without changing the harness.
It took me close to 6 months to figure it all out.

Ford every year changes a few wires in the wire harnesses or changes
how things are grounded

In my case, i could NOT code scan, and AC would NOT work

i ended up swapping a couple of wires at the C130 connector and
hot wiring a ground to chassis to fix the A/C.

I ended up getting a Multi year CD manual on Ebay, and printing out
both years schematics and trying to figure it all out. Took forever.

In retrospect, i would have been easier just to get a whole harness
from a Upull yard than go through the issues i had.


bob
 

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I Feel your pain. I put a 96 Vulcan into a 97 without changing the harness.
It took me close to 6 months to figure it all out.

Ford every year changes a few wires in the wire harnesses or changes
how things are grounded

In my case, i could NOT code scan, and AC would NOT work

i ended up swapping a couple of wires at the C130 connector and
hot wiring a ground to chassis to fix the A/C.

I ended up getting a Multi year CD manual on Ebay, and printing out
both years schematics and trying to figure it all out. Took forever.

In retrospect, i would have been easier just to get a whole harness
from a Upull yard than go through the issues i had.


bob
+1

You might be seeing a problem where either the harness connects to the PCM, or the harness joins on that bracket on the tranny. The pins might be different from one side to the other between years.
 

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+1

You might be seeing a problem where either the harness connects to the PCM, or the harness joins on that bracket on the tranny. The pins might be different from one side to the other between years.

The multi pin connector that connects the motor to the trannie is C130.
1/2 is the motor side harness. the other 1/2 sits on top of the trannie drivers side connected to a hard bracket. So if only the motor was changed, every thing else from 1/2 of C130 on the transmission to the firewall are unchanged.

If one was brave enough to rewire it, you need to strip back the wrapped wire guard just behind the motor side C130 to get access to the wires.
then cut and splice the wires at that point.

From the schematics, you need to ID the Pin numbers as well as the color code on the wires. Somewhere on the site, i had posted the C130 codes
for the 97

bob
 

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You guys work TOOOO hard. Swap the few sensors over from the old engine to the new, same for intake parts needed, everything else "should" be the same install engine, no wiring nightmare AND a lot less down time.
 

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Well, i have a 98 hard manual and did some checking. Good news bad news. Do you own research to verify this.
I think in 98+, they went to a DTR (digital transmission range selector)
on the trannie instead of the older TRS (transmission range selector.

They both basically do the same thing, so whats the big deal your thinking?

Well, the digital sensor uses more pins i think and works differently
check this link out for some more info:

http://www.becontrols.com/tech/tcsdtrupdate.pdf
www.motorcraftservice.com/vdirs/diagnostics/pdf/obdsm986.pdf

What i think you issue is, the motor side wire harness is wired for a DTR and NOT the TRS you have on your 97. My 98 manual shows 4 wires from the DTR on connector C130.

ckt 237 O/Y PCM PIN 3
ckt 315 P/O PCM PIN 40
ckt 199 LB/Y PCM PIN 50
ckt 971 PK/BK PCM PIN 64

Might be some issues with the VSS also.

so you need to see what the wiring differences and any grounding
differences are. Or just change the harness
 

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You guys work TOOOO hard. Swap the few sensors over from the old engine to the new, same for intake parts needed, everything else "should" be the same install engine, no wiring nightmare AND a lot less down time.
I wish it were always that easy. I can tall you for a fact that when
i put my 96 engine and harness into a 97 that the motor harness WAS different. Thats a fact. and it DID cause issues. Sensor swaps would NOT
fix it. Wiring change did. If you don't beleive me, get the wiring diagrams,
compare them, and tell me i was wrong.

as for as the issue here, more research needs to be done
It looks like it may be a DTR/TRS wiring issue. Somewhere in that time
frame, the trannies went from TRS to DTR and they don't work the same.


If i EVER do a engine swap again, it will ONLY be with the correct year
wiring harness on the donor.
 

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Yes Dub.

Bob, I've done many engine swaps and none have been very difficult, granted they've all had their own share of problems, but none really "hard". I can understand changing an entire harness if ones been burnt or someone has "taken a chainsaw to it" and it's completely unusable. Other than that I see no reason to mess with it. Granted there are some differences between models 9 times out of 10 you can simply pull a sensor off the "old" engine, stick it on the replacement, and move along. I've got an '07 engine sitting out front in a '93GL that proves that. I've got an '01 engine in a '95 Ranger that runs perfectly as well, and neither required any rewiring or wiring modifications. The OP stated he swapped in a
98+ vulcan motor in my 97
and what sounded like the original trans FOR HIS car. Now if he used the OE trans, WHY did he think he needed to change the harness to something different? This sounds like where his problems are coming from unless I've read something incorrectly. The vulcan engine for the most part has remained unchanged from '86 - '07. Yes they've changed sensor plugs and trans plugs, and eliminated the distributor, and stuff like that. The OP only went 1 or two years difference in model years, and it's not like he stuffed an LSx engine into it, so again, I ask why change the harness? He could have simply swapped some sensors, maybe the upper intake if need be, and dropped it right back in. Would he have had a CEL, I dunno, maybe, maybe not. Did he have any lights on, before the swap? If not then one could assume that all the sensors on the '97 engine(OE) were good, and reusable. But, he used the '98+ sensors and harness, which may or may NOT have been any good. Unless it's put back the way it was no-one will ever know. I'm not saying you or anyone else did anything wrong in the way you did things, simply that it may have been easier a different way. I'm also not saying that "MY way" is superior or any more right. There's a saying, you wash your nuts your way, I'll wash mine my way. Either way I'm sure they'll be clean, but it won't take me six months. Please don't misconstru anything I've said here, I'm just trying to pass along a little of what I've learned and experienced in 25 years of wrenching.
 

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Yes Dub.

Bob, I've done many engine swaps and none have been very difficult, granted they've all had their own share of problems, but none really "hard". I can understand changing an entire harness if ones been burnt or someone has "taken a chainsaw to it" and it's completely unusable. Other than that I see no reason to mess with it. Granted there are some differences between models 9 times out of 10 you can simply pull a sensor off the "old" engine, stick it on the replacement, and move along. I've got an '07 engine sitting out front in a '93GL that proves that. I've got an '01 engine in a '95 Ranger that runs perfectly as well, and neither required any rewiring or wiring modifications. The OP stated he swapped in a and what sounded like the original trans FOR HIS car. Now if he used the OE trans, WHY did he think he needed to change the harness to something different? This sounds like where his problems are coming from unless I've read something incorrectly. The vulcan engine for the most part has remained unchanged from '86 - '07. Yes they've changed sensor plugs and trans plugs, and eliminated the distributor, and stuff like that. The OP only went 1 or two years difference in model years, and it's not like he stuffed an LSx engine into it, so again, I ask why change the harness? He could have simply swapped some sensors, maybe the upper intake if need be, and dropped it right back in. Would he have had a CEL, I dunno, maybe, maybe not. Did he have any lights on, before the swap? If not then one could assume that all the sensors on the '97 engine(OE) were good, and reusable. But, he used the '98+ sensors and harness, which may or may NOT have been any good. Unless it's put back the way it was no-one will ever know. I'm not saying you or anyone else did anything wrong in the way you did things, simply that it may have been easier a different way. I'm also not saying that "MY way" is superior or any more right. There's a saying, you wash your nuts your way, I'll wash mine my way. Either way I'm sure they'll be clean, but it won't take me six months. Please don't misconstru anything I've said here, I'm just trying to pass along a little of what I've learned and experienced in 25 years of wrenching.
This whole conversation should be about education and learning whats
what. I have got lots of good information here that has helped me fix
my car and keep it running on a shoe string budget at times.

I will use your own example. When you put the 07 engine in the 93, you
certainly did NOT use the 07 harness. What i would have done (and
assumed you did) was take the entire intake off the 07 and put the 93's
intake and wiring harness on it. and taken off the dist sensor and put a
distributor in it.

I am sure you did not put a non ranger harness in the ranger either.

The issue here is using a engine wiring harness NOT from the year of car
your using it in. Its a FACT that the wire harnesses are NOT always the
same year to year. Close, but NOT the same.

So you have two choices if you have issues, use the proper wire harness
for the year of car your using, or modify the non proper year to make it
work. changing sensors does nothing to the wiring in the harness if its not correct.

In my case, i bought a 97 Vulcan Gl with bad engine. I had someone drop a good 96 engine in it. Unknown to me at the time, he left the 96 harness on the motor, so the 97 had a 96 Vulcan and the 96 wire harness on it. The car refused to code scan, and the AC would not work. But it ran and drove, so i drove the car during this time even though it had issues. I tried to find out on line what the issues were, but could find no information.

It was only then that i got a OBD2 scanner, factory CD manuals, and
printed schematics and messed with it. got the code scan back quicker by swapping a few wires at the C130 connector. changing sensors would not have brought back the code scan. The AC i did not need at the time, so i let it slide until much latter when it got hot. It was then that i discovered the final part of the puzzle that the AC clutch grounded differently between the 96 and 97 wire harnesses. I ran a separate ground off a cut wire at C130 connector and it fixed the AC. It took a lot of studying partial schematics and trial and error to finally get it all working 100%. Other people had the same issues since and i helped them get there cars going. There is a prior thread on this if you want to look it up.

By the time i realized i had a harness issue, the dude that dropped my motor in had disposed of the 97 core so it was too late. Thats why i recommend using the same year harness on the engine. tracing down all that wiring is time consuming and confusing. It can be done, but you need the resources and time to do it.

Since its not my car, i am not going to devote my life to finding all the issue. But it does seem in that time period, the transmission range sensor (TRS) changed to a digital version (DTR)(98+?) The sensor on the trannie is still the TRS because its the original 97. That should be OK. the PCM is the proper 97, so that should be OK. So what is the only difference? seems the wire harness on the engine. That harness connects the TRS or DTR to the PCM. so if there is any wiring difference, the PCM will sense an issue and throw a trannie code.

Since it seemed the sensor harness change did not solve the problem, i would either put the original year harness on the donor engine, or get all the proper year manuals, print the schematics, and figure out and change the wiring. My guess is the newer harness on the engine was wired for the DTR, and that one or more wires are different or that there was a grounding change somewhere on the harness.

I wish the poster the best of luck in solving his issues
 

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I had someone drop a good 96 engine in it. Unknown to me at the time, he left the 96 harness on the motor
Sooo, if the idiot that did this would have swapped sensors, YOU most likely would NOT have had to spend six months and all kinds of energy getting your car back on the road, right?
 

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Sooo, if the idiot that did this would have swapped sensors, YOU most likely would NOT have had to spend six months and all kinds of energy getting your car back on the road, right?
I guess you did not carefully read ANY of my posts. Unless your calling the
engine wire harness a "sensor", (which its not), no sensor swap would have
made any difference. I repeat, the engine wire harnesses were DIFFERENT
on a few of the wires. Yes, it bolted right in and connected. NO, it did not work 100%. Yes, the car ran and drove that way for a long time.

I guess you could explain to me how swapping sensors is going to change
how the AC clutch is grounded. Or make the OBD2 connector work when one of its wires did not go where it was suppose to.

Hindsight is 20/20. Once the car was running, i drove it and worked on it
as i could. That only took a few days after i got the car back from the swap. It took a while to figure out what he did with the harness.
And it took a while to figure out the harnesses were NOT electrically 100% the same. Then, it took time for me to get the manuals/DVD, print them out and figure it out. I had a running car, so it was not a big deal that it was not perfect. Irritating, but it got me to work. The AC took the
6 month periods because i did not need it at the time. How many here do not have working ac all the time? I'll be quite a few. How does one know
if the harnesses are not the same? Its something your not going to see
in the factory manual. You have to do the detective work on the electrical
schematics, change the wiring and see what happens.

The original poster said what he did. and asked for what to look for.
Can you tell him what sensors to swap now to fix the issue?

I at least gave him a lead to follow of possible wiring issues and why.

You can make fun of me all you want. But the guys i helped get there AC
back on line after there harness issues are not laughing.

If i can ever find my DVD, i will post the wiring differences if i can find them. i had the 98 manual on hard cover, but my 97 was only on disk

maybe we both can help this guy get his bull back on the road with
useful information
 

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Bob, I'm not in any way making fun of you. Though you're still insisting the harness without a doubt HAS to be changed, just because the enigne is coming from a different year model, and that's not necessarily true. If your guy would have left your harness in your car, all he would have to have done was swap a few sensors from block to block and been done. Then it would not matter how one component grounds because it would have been the harness for THAT car. NO? All I was asking is WHY the OP felt it was necessary to swap harnesses. Just because it was on the new ('98) engine to begin with?? It was in my opinion NOT needed, unless the harness for HIS car was messed up. In other words, strip the wiring OFF the '98 engine, compare the sensors between the two engines, swap the sensors FROM the '97 that need to go ONTO the '98 to make it work in the '97 car WITH the '97 harness. No muss no fuss. That's exactly what I did on my '93 with the '07 engine.


Either way it comes down to we both did what we thought was the correct way to handle our particular situations.
 

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Bob, I'm not in any way making fun of you. Though you're still insisting the harness without a doubt HAS to be changed, just because the engine is coming from a different year model, and that's not necessarily true. If your guy would have left your harness in your car, all he would have to have done was swap a few sensors from block to block and been done. Then it would not matter how one component grounds because it would have been the harness for THAT car. NO? All I was asking is WHY the OP felt it was necessary to swap harnesses. Just because it was on the new ('98) engine to begin with?? It was in my opinion NOT needed, unless the harness for HIS car was messed up. In other words, strip the wiring OFF the '98 engine, compare the sensors between the two engines, swap the sensors FROM the '97 that need to go ONTO the '98 to make it work in the '97 car WITH the '97 harness. No muss no fuss. That's exactly what I did on my '93 with the '07 engine.


Either way it comes down to we both did what we thought was the correct way to handle our particular situations.
As long as the end result is a working car, the solution was correct.
the motor harness is part of the motor. so when it was pulled out,
it went with the old engine. the donor from the 96 was put in with what
looked like the same harness. Until i had issues, i thought it would work
too. Wrong assumption on my part. you really almost need to pull the upper plenum off to change the engine harness once it snakes through it.

Getting back to the original guys issues, the red flags always go on for me
when things change under the hood. 97 was the last year for the CCRM
before they went to discreet relays. As far as i can tell, it was also the last year for the TRS analog transmission sender, then they changed to the digital sensor in 98+. so there are two major electrical changes potentially under the hood.

now, he has a 97 underhood chassis harness connected to a 98+ motor harness which is then connected to the 97 PCM. If you had the 97 schematics, you could measure continuity on every wire from the TRS sender to the PCM wire connector and make sure every wire goes to the right pins on the PCM.

At this point, i am not sure if this is an issue or not. It could be something
as simple as a bad TRS switch, which are know to cause issues

The limited checking i have done shows the TRS and DTR work differently,
to me that raises a red flag to check out the wiring there to make sure
all pins from the TRS get to where there going on the PCM. If he had changed the motor wire harness, to the 97 harness, it would be a non issue unless the harness was damaged lik you suggested earlier.

I think were on the same page, he should have used the 97 motor side
wire harness and sensors on the donor motor.

If he does not have the 97 harness anymore, he is going to have to find
a junk yard one, or figure out the wires that are different like i had to do.

What i have to do on mine now is a right front wheel hub, which is scarring
me that i am going to have issues and disable the car for awhile. Some people report them popping right off, others say they beat on them for hours. I have a new hub and a hydraulic jaw puller, but i am still concerned.
 

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Discussion Starter · #20 ·
I have been away awhile... glad this thread took off.

I did have problems with the CPS and the VSS, but those are both rewired and working properly. (Had to convert to original 3 prong CPS and wire it into the 98 harness... really easy actually)

The trans will still not go into overdrive. Works flawlessly in every other regard. I am sure it is because the sensor is not seeing the right voltage due to the harness difference. These are only 2 wires, a 12v power in and a signal out to pin 64 on the PCM.

I am going to go measure the voltage in, and make sure the wire actually goes to the right pin. It should be one of those 2 things.

In the future.... just use the right model year harness... much easier. But, I'm not tearing the whole thing back apart to switch harnesses. Wiring in a few changes isn't really that tough, and is fun to do.

Brian
 
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