I have read a number of threads addressing the concern of sometimes starting, sometimes not starting.

I have a 1994 F-150 5.0L 2x4

I am reading in threads about a PIP sensor (mounts inside the distributor?) as well as an ICM (ignition control module, mounts outside the distributor), according to everything I read one of these may be my problem so I call my ford parts dept. as well as my local parts house and they have never heard of a PIP sensor.

The guy at the Ford dealer only knew of the Ignition control module (mounts outside the distributor)

The guy at my parts house assumed the PIP sensor was the ICM, and had no idea of any sensor that mounted inside of the distributor?

I have searched Google images and found separate images for both the PIP and the ICM and it's obvious that the PIP would mount inside the distributor and the ICM would mount outside the distributor.

I believe the PIP sensor is not sold separately by most parts houses, therefore they have no knowledge of the PIP as an available part.

Can anyone Please share with me where I may find a PIP sensor?

Can anyone Please share with me a parts source that would sell a PIP sensor?

Thanks in advance, Scott

 

The PIP (Profile Ignition Pickup) sensor is also referred to as the stator or ignition pickup. For reference: Fuel Injection Technical Library » Stator (RPM)


Motorcraft part number# DU50.

 

Any auto parts store will sell the PIP sensor but it is listed in all of their books as the Stator Assembly. The PIP mounts on the the Stator Assembly plate and yes it goes inside the Distributor. But you have remove the distributor and take it all apart to replace the Stator Assembly.
Do not buy a rebuilt distributor, only a new one or have the Stator Assembly replaced inside of yours. Most all rebuilt distributor have bad PIP sensors in them.

As far as the ICM (Ignition Control Module) it does mount on the drivers side fender and for your truck you must buy one that is Black in color.
Most auto parts stores and some Ford dealers will try to sell you the wrong one that is Gray in color.
But your truck starting in 1994 is only wired for the Black one. The PCM Computer is also setup and wired to just run with the Black one.

 

Thank you rla2005, for the clarification.
In your opinion ( if you had no test equipment) witch one would you replace first?
Also to replace the Stator Assemble must the distributor be removed?

Thank you, Scott

 

Reread my post after refreshing the page as I did edit it not knowing you were logged in.

 

Thank you so much subford for the information.

In your opinion ( if you had no test equipment) witch one would you think would be the most likely cause ? Which to replace first?
The Stator Assembly or the Ignition Control Module?

The symptoms were:
Truck would run great and out of nowhere it would not start. Sometimes it would try to start, idle rough and die.
A few minutes later it would start and run fine.
However once running it would never stall, only fail to start from time to time and it never seemed to matter if it was cold or warmed up.

 

MOST times if it is the PIP sensor,it will only die after it is warmed up and not restart until it cools off some. Have you checked fuel pressure when it is running bad/won't start?

 

checked fuel first thing, changed filter & checked pressure, problem is defiantly no spark. I guess I'll try replacing the Stator assembly first.
Thanks guys for all the assistance & I'll keep posting on the outcome.

 

It is a guessing game and a matter of catching the problem when it occurs to determine if the PIP is the root cause or the ICM. They both have a history of equal contribution to the root cause.

The Ignition Control Module can be tested but sometimes that is inconclusive. The black remote mount ICMs are not know to fail like the distributor mounted gray ICMs. I chased a PIP problem for months on my old 1993 F150 Lightning before I finally found it was the PIP (stator) inside the distributor. Back then I was not aware of this common problem and how to troubleshoot it. I am older and wiser now.

There are several write-ups on the web of how to troubleshoot this problem and separate the PIP operation from the ICM. But it does require a few tools and catching the problem while it is occurring. If you had an oscilloscope you could probably rule out the PIP in a short amount of time. Sadly I no longer have one of those :-(

 

Neither.
To me it sounds like a bad computer as that is the way they act. The PIP and ICM just do not act that way.
To test the next time you have no spark pull out the SPOUT shoring jumper bar and see if spark returns. If spark does return what you need to do is pull the computer out and open it up. Look at the two or three electrolytic capacitors. I think you will see one or more are leaking.
Replace the electrolytic capacitors and your problem should be fixed.
Or go to a salvage yard and get another one. From reading on here I do not trust rebuilt computers any more as most of the time you are getting someone else's problem.
I like to unplug the computer to check for the return of spark but I have herd that a lot of posters have tested it by just unplugging the SPOUT.

 

Alright subford I think your onto the real problem.
I have found the computer behind the drivers side kick panel, I have removed the e-break and kick panel and am having a time removing the computer.
their is a wiring harness plugging into it from the engine compartment with a bolt in the center of the plug. I'm assuming if I remove the bolt the wiring harness plug will come off, however after a few turns of the bolt (counterclockwise) it feels as if it's getting tighter???W.T.H.???
I just wanted to check before I powered through removing the bolt.
Any words of advice?
And thanks again for all of your help so far.

 

They tend to provide resistance all the way out, so that's "normal". What year is your truck? '87 - '91 the PCM can come out form the cab. '92 - '96 it has to come out from the engine bay, which requires the splash-shield to be removed (at least partially).

 

The computer is only removed from under the hood through the gap between inter and outer fenders.
You have to remove some small screws around the where the fenders meet and then pry a gap with a broom handle to get the computer through.

You work the plug up and down as you back out the center bolt of the computer plug. After it is unplugged there are two small nuts you have to remove, one above and one below the plug.
Then take the computer out.
If you block the truck up and take off the front wheel it sometimes helps and will give you more room.

 

Subford, Once again you are right on the money, before I read your last post I determined I would have to remove a few screws from the internal fender molding to get the extra inch needed to remove the module.
I remember seeing a post a few days back with pictures and capacitor values that explaned the process, would that happen to be your post?
If so would you please share the link to that post?
Regardless, Thanks again for all of your help & if I can I'll try to video this process & post on utube for the next guy.

 

This may be the thread you are talking about:
https://www.ford-trucks.com/forums/1...l#post12723818

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