I get no spark, and the fuel pumps do not run when the key is turned to the on position. I grounded the fuel pump lead. Both pumps run when I do so. I tried to pull codes KOEO, but could not do so. I smell burnt electronic smell in the cab and under the hood. I cannot see evidence of burning wires anywhere under the hood or in the cab. I also varified the operation of fuel pump relay, EEC relay, both are ok. I get a click, I feel the EEC relay when it energizes when key is turned on. I also swapped these relays to make sure. Any suggestions would be appreciated.

 

The fuel pumps use a fusible link near the battery. Check it and make sure it didn't get fried somehow. That could account for the burning smell.

 

Fusible link is fine,also the fuel pumps will run if you ground the fuel pump lead on the Data Link Connector.

 

The Fuel Pumps are not running and you have no spark because the "PIP" pulse is missing.
The "PIP" pulse is missing more than likely because there is no power to the Ignition System and you need to find out if the PCM is getting power.
Test light trace time, divide and conquer.
Good Luck, sounds like you are going to need it.

 

power is getting to PCM,I consulted my Haynes manual to learn how to check for PIP signal. I have PIP supply voltage 12 v at the Distributor. Output voltage when cranking should be 3.0-8.5 volts. according to Haynes. Mine read 1-2 volts. I unplugged ICM and checked voltage again 4-5.5 volts, Haynes says ICM is shorting PIP, what do you think?

 

Yes it is more than likely you have a bad ICM, you can check it by measuring from (COIL) to (ICM PWR) on the ICM with the ICM disconnected and if it is less than 10K with your ohm meter it is bad, I would replace it any way.
IF the PCM is not getting a good PIP it will not turn on the fuel pumps (other than initially when the key first goes to the run pos.) and fire the injectors or the ignition coil.

 

If the PIP goes you'll still get spark I beleive.

 

Without PIP the ICM will not fire the coil and PCM will not know how to control the SPOUT.

My ERROR above about the PCM firing the coil but the result is the same.

I will be more precise next time, sorry.

 

Subford,
Sorry If I came across bad or rude. I just want to learn myself, and give good advice when I can.

It my understanding that PIP is feed directly to the EEC which then directs the TFI module when to fire the coil and in absense of a pip signal will attempt to fire the engine anyways.

I would like to know if there is or isn't spark without a PIP signal.

Thanks,
Popa Tim

 

You are right if he has the TFI module mounted on the Distributor and it is a good one and you lose SPOUT control and have power, it will fire base timing.

I may be wrong but I got the impression that the truck in question had a remote mounted ICM and that is why I said what I said. If I am wrong please let me know.

It's my understanding that PIP is the same as the points were in the old Distributor system but now its a vane switch that is in a encapsulated package consisting of a Hall effect device on one side and a permanent magnet on the other side.

The ICM (or TIF) is the same as the Transistorized Ignition System Module except now it can be controlled remotely by the PCM though the SPOUT.

On some engines the PIP comes from the CPM sensor.

 

I am sorry, I should have typed the following, I unplugged the PCM and the voltage read 4-5.5 volts, which is in range.Haynes says PCM is shorting the PIP signal.

 

Where are you reading this voltage at, the plug PIP pin?
Is your ICM remotely mounted or is it on the side of the Distributor?

 

I am reading voltage at pin #1 wire at distributor wiring plug. The ICM is remote mounted. The engine is being turned over when taking this reading.

 

I think Haynes is right, the only other thing on the PIP wire is the PCM. Change it out and if the replacement screws to the heat sink, make sure you put a lot on heat sink compound on it or it will go back out. That’s is why they fail, the old heat sink compound dries up and the ICM overheats.

Good Luck

P.S. please let us know how it turns out.

 

Thanks for the help, i will let both of you know how it goes.