Srtz0680

Hello, Folks. I have a 2001 Ford F-150 4.6 L V8 4x4 AT Extended Cab that is not starting. I am considering trying out a new PCM as the issue leads me to believe that the issue may be the PCM. Now then, the PCM part number for my truck is 1L3Z-12A650-AXB.

I have found a used PCM online that is for a pickup very similiar to mine, except that it is a Crew Cab, NOT the Extended. The part number for the potential replacement is 1L3F-12A650-LD.

My question is this: Will this PCM from the Crew Cab work for my pickup if properly programmed and installed?

Thanks in advance, and my apologies if this has already been answered before.

akdoggie

The 2 numbers you listed are compatible swap numbers. Both numbers show using the same replacement computer. Rebuilt ecm runs about 180. You would still have to have your computer flashed for the PCM to allow a start and run due to PATS (remaned or eBay units). Otherwise, you will have a flashing theft light and no engine starter engagement. Is the engine turning over and won't fire off, or is it just dead to the starter but you have full gauge and operational idiot lights and CEL?

Srtz0680

First off, I thank you kindly for responding and helping me, Sir.

As for the truck - ignition on, it turns over, but never fires up. At this point, I have replaced fuel filter, fuel filter replay, crankshaft position sensor, and camshaft position sensor - still no start.

*I DID NOT change the fuel pump, because when I check the Schrader Valve on the fuel rail, it always has discharge.

My guess via the dreaded proce$$ of elimination is that the PCM may be the issue, Sir.

akdoggie

You can have 5# of pressure at the Shrader valve and spray everywhere, and it won't start. It won't even crack the injectors if the pressure isn't sufficient. I'd put a set of gauges on the engine and know what the fuel system is doing. OR or AZ have them for rent. You need 40# at the valve to operate correctly. Check it out before you condemn the ecm.

Srtz0680

So, I put a fuel pressure gauge on the rail, and upon turning the ignition on, there was 0 psi. Upon turning the key, and turning over the engine, although it DID NOT start, the pressure gauge still remained at 0 psi.

I initially thought this would indicate that the fuel pump was the culprit because there was 0 psi regardless of the ignition being on and the engine turning over repeatedly.

Should I stick with the guess that the fuel pump may be the culprit? I do have a fuel pump on hand already as well.

akdoggie

When you first turn the key to the on position, do you hear your fuel pump engaging for 2-3 seconds? If not, check power to the pump. If you have power and no pump engagement then you've found your problem.

Srtz0680

Yessir. Each time you turn the key to the ON position, I do hear the whine, and then a thunk sound.

Auto Zone gauge read 0 at all times, I suppose I should trust what the gauge said despite the Schrader discharge.

It makes sense to me as you pointed out, that while there was discharge from the Schrader Valve, perhaps the pressure is not enough and/or the pump is not maintaining the pressure.

Srtz0680

Went ahead and replaced the fuel pump. She still didn't start. Upon turning ignition on and attempting to crank the engine, the 'THEFT' alert light on the dash illuminated a solid red.

Next, we accessed the steering column, and checked all connections for tightness. Upon retightening everything, we reset the pcm, and attempted a start, and she FIRED UP and remained running.

After turning the engine off, and immediately attempting to turn her on, she never started again. We then reset the pcm again, but still no start.

Very perplexing...stumped, although it was nice to hear the engine roar again after so much silence!

I am going to search for the 1L3Z...AXB pcm...

akdoggie

How are you resetting the pcm/

Srtz0680

A buddy plugged a computer into the ODB port. I suppose it may have been an ODB tool. Anyway, he said that he cleared the pcm and "reset" it that way.