[cloutierthedj]

Any help is appreciated
My truck is slipping slightly around 45-55MPH. The engine RPM rises about 300 RPM then back down. Almost like the torque converter is slipping. I visted a local shop and had them read the codes and I got a 62,63,67. I adjusted the FIPL but when I set it for 1.1V closed throttle, once I go to WOT and back the meter reads about .6V If I barely touch the accelerator pedal it jumps back to 1.1(ish). What do I do??????? Thanks in advance

 

[cdnsarguy]

OK when you set the FIPL was the engine warm, was your idle speed set to curb idle 650rpm in gear before starting the testing.

 

[cloutierthedj]

The truck was at normal operating temperature. Maybe I understood the process wrong. I was under the assumption that the truck is off, but the key is in the on posistion, (truck not running at this point). I put the test lead (red) of my meter into the rubber boot next to the center wire, and hooked the other test lead (black) to the negative battery post. Is this correct? I had read some other posts and that is how I understood the test to go. As far as the idle goes, in gear the truck idles at 650-700 RPM, about 800-850 in park.

 

[cdnsarguy]

You have done the FIPL reset correctly from what you say. Sorry if my wording confused you in my last post. Yes key on engine off (KOEO) is correct. When moving the throttle move it slowly you are looking for dead spots in the potentiometer.

What color is your FIPL........

DIESEL FIPL SENSOR INFO
DATE 1992
REASON
Early Black FIPL has High Failure Rate
RECOMMENDATION
Always replace the black colored early FIPL or any colored FIPL having 60 thousand or more miles with the late gray colored FIPL.
PART NUMBER
F2TZ-9B989-C

 

[OkieGringo]

The 300rpm fluctuation is the TC locking/un-locking. The trans computer is VERY sensitive to the FIPL voltage, as you've already noticed. I recommend replacing the FIPL, it's cheap at most auto parts stores. There is a idle speed screw on passenger side of IP, but you hafta rotate the throttle shaft to get at it. Also, the FIS (Fast Idle Solenoid) plunger is adjustable (1/4" open end wrench). It might be out too far at warm idle. Set the idle screw after turning in the FIS plunger. Then when engine is cold, reset the FIS plunger to get the rpm you want. Check the electrical connector sequence to IP. If FIS is connected before the CES, the FIS will always be on.
To check the connections to the IP, here's what you need to do. Turn on key to 'run' position. Check the main wire that comes from the loom to the IP (injection pump), does it have juice. The wire runs to the FSS (fuel shutoff switch) connector first, then to one side of the Cold Engine Switch(two-prong sensor, located in hole behind the upper radiator hose connection). When the engine is cold 'juice' will pass thru the sensor, if the sensor is good, and go to either the FIS (fast idle solenoid) or the CTA (cold timing advance), then to the other. If the engine is cold and sensor is good it will be 'closed' and allow 'juice' to get to the FIS plunger which holds the idle speed up. If FIS plunger is working, but not pushing up far enough, use a 1/4" wrench to turn/extend it until the idle speed is ~1000 rpm. The CTA (cold timing advance) near the spider/distribution end of the IP 'advances the timing' to make engine run smoother/run cleaner/less smoke. The Cold Engine Switch opens/shuts off the electricity to the FIS and CTA after engine reaches 112 degrees, and engine speed/rpm will/should drop to ~650 rpm. If these three items are working correctly, when you go to start engine, hold the throttle pedal at least 1/2 way to floor to allow the FIS plunger to 'set' itself. Use a test light to check for electricity/juice at each of the solenoids, FSS, FIS and CTA. Let me know if this helps. Good luck, OkieGringo

 

[cloutierthedj]

The FIPL is black. As for Okie, the fast idle works great when cold. I'll tell a little back story here to see if this helps anyone. I had the truck into a local diesel shop, diesel's are all they touch, they are however into truck pulls and the "black smoke blinders", where a truck in front of you blinds you with it's black smoke. They replaced the IP on the truck as well as the fuel lift pump. When I got the truck back it wouldn't shift until yellow line, (the line before red). I work at College with an automotive department and had them readjust the idle, (they had it at 950RPM), as well as the FIPL, they turned it down to shift smooth when you're putting along, and shifts harder when you romp it. I pull a small enclosed trailer (5'X8') that weighs about 3000#.

 

[cdnsarguy]

My best advise would be take it back to the Blinders and have them fix it for free.

 

[blackestate]

There is a little adapter on the end of the rod coming out of the IP that goes into the FIPL. Make sure that is not loose, that could cause the random change when returning to idle?

just an idea...

 

[cloutierthedj]

A BIG THANKS FOR EVERYONE'S HELP/ADVICE. I finally got around to replacing the FIPL, (had to order from Napa) and that seems to have taken care of all the problems. Thanks again for everything.

 

[swhitney133]

Change the fipl or tps which ever suits your fancy. My tps was set fine but when I checked the ohms with the new one it was very close but off by a little bit. Once I set the new one the trans runs fine now, I thought the trans was spent but after cleaning all connectors and replacing the tps it is fine once again.