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Discussion Starter · #1 ·
This is on my 87 Taurus 3.0L

So for my KOEO test, I received a code 88 and 11.
--88 I know is the cooling fan circuit fault. The cooling fan does turn on when I click on the AC system. But as the temp rises sitting in traffic, it will not kick on.
Guessing the infamous relay box on the header panel is to blame.

For my KOER, I received a code 42.
--As was suggested to me by Jeff K, if I detected the smell of fuel or the sight of fuel coming from the vacuum line that runs from the fuel pressure regulator to the upper intake manifold, then I need to replace the fuel pressure regulator.

Based on the way my car behaves...where it smells like it's running rich at idle, and light throttle applications will not even make the car accelerate...no engine revving or nothing...it sounds like the ticket. Plus, when I removed the vacuum line after running it, it smelled like gas. No sight of gas coming out of the FPR when running or sitting.

So the Ford shop manual says to remove the old regulator by relieving the pressure (remove gas cap and using Ford/Obsolete tool at the fuel rail). Since tool is no longer made, how do I relieve fuel pressure at the rail? How does that Black plastic cover on top of the release remove?
 

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If the port where you relieve the fuel pressure is a schrader valve, then its like a tire valve....where you unscrew the cap...and attach the "tool" to relieve the pressure and catch the excess gas. Some people I know don't use a tool on a schrader valve. They put a rag over the valve and press the pin in the middle of the valve with a screwdriver...using the rag to catch the excess gas.

If its not that type of port, then I don't know how. Perhaps you could remove the relay to the fuel pump, start the engine and starve it for gas until the pressure is gone and the car stalls :dunno:
 

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Nick, just let the car sit overnight and the pressure will drop low enough that very little, if any gas will spray around when removing the FPR.

Is the 87 a 2 speed fan? First thing I would do is jumper the fan winding (windings if 2 speed to the batt to be sure both speeds work. If not, time for a new fan motor.
 

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Discussion Starter · #4 ·
Not sure if the fan is a 2 speed, I guess it is?. I know there are just 2 wires coming off of connector. The car has 1 single fan, unlike later model Tauruses (Taurii?). I know the fan kicks on when the AC is activated, but not sure how I would test the fan "windings"?

Cool so I will replace the FPR tomorrow then, I haven't cranked the 87 up since last weekend, so I can pop it off with ease.
 

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Fan

Not sure if the fan is a 2 speed, I guess it is?. I know there are just 2 wires coming off of connector. The car has 1 single fan, unlike later model Tauruses (Taurii?). I know the fan kicks on when the AC is activated, but not sure how I would test the fan "windings"?

Cool so I will replace the FPR tomorrow then, I haven't cranked the 87 up since last weekend, so I can pop it off with ease.
The '87 has a 2 speed fan with a resistor for the low speed. As I remember it is on the engine block. Low speed is for A/C and engine temp over some value, like 220 and then the high speed kicks in at some other higher temp like 235. On those models you could put in the simple code checker and it would exercise the fan, first on low, then on high speed. You could just listen and tell if they were working.

Oh the good old days. NOT

-chart-
 

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Discussion Starter · #6 ·
I neglect to check the FSM sometimes. It says exactly what you said chart. 2.5 ATX and all 3.0 models have the 2 speed fan, MT-5s have a 1 speed fan. And a dropping resistor in series for low speed on the 2 speed fans.

Low speed turns on @ 215F, off at 210F. High speed turns on at 235F, off at 224F.

What should my next step be? If I need to jumper the fan windings as suggested above, how do I do this?
 

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Nick, refresh my memory.... is code 88 EDF (low speed) or HEDF (high speed) fan code? If its a low speed fan code, check the resistor. If fan runs on high speed, fan windings are good. As Chart said, fan should run on both speeds during KOEO test. PCM looks for system voltage drop due to fans high amp draw when fan runs at each speed during KOEO test. If PCM doesnt see the expected volt drop, it set a fan code.
 

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Discussion Starter · #8 ·

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Nick, I checked my 87 Engine/emissions diagnosis manual (H manual) for code 88. It is a EDF code that only applies to 3.0 EFI and 2.5 CFI engines. It also appplies to the Turbo Coupe, but the code number is different from the Taurus.

Do the following: IRCM plugged in. Disconnect EEC 60 pin connector. Turn key to RUN. If all is well, EDF should run on low speed (as well as lo speed relay in IRCM click shut. If relay doesnt click / fan run, check EDF trigger circuit from IRCM to PCM for a short to ground. If relay in IRCM clicks but fan doesnt run, suspect the fan resistor.

The logic behind this (from experience, not from the manual): PCM runs the low speed fan when the trigger circuit from PCM is OPEN, not GROUNDED as every other activator is. WHen PCM grounds the trigger circuit, EDF turns off. This is why disconnecting PCM with key on should run the fan (trigger circuit is open). I believe this is a "fail safe" system, so if the driver in the PCM fries open (most common failure mode), or the trigger circuit from the PCM to the IRCM is cut, the EDF will run on low speed all the time to keep the engine cool. If the trigger circuit is shorted to ground, the fan will never run, however.
 
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Discussion Starter · #10 ·
Per your instructions, I did as mentioned above (removed the 60 pin connector). Turning key to run had the fan run at low speed. Was not able to detect fast enough if relay clicked since I had to run back to front of car, but since the fan ran I guess it's OK.

This reminds me when the 3 wires that are "rednecked" onto the ground terminal that attach to my battery had become separated, causing the car to not start, until I tightened the bolt down. The fan kicked on to low speed when this had happened. Hmmmm...
 

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Sounds like the IRCM and fan are working correctly.
 
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