Hey fellas,

I recently purchased a non-running '95 F150 XL with the 4.9L engine and the Mazda manual transmission. After all the reading up I've been doing, I suspect that the ECM is the likely culprit for the non-running condition. In my search to find a replacement ECM I've found that there is a large multitude of options that range in price. I obviously will need to source a manual transmission version, but don't really know how to discern *which* of the part numbers I need. My search on Autozone allows me to sort by manual transmission - but I'm still left with 12 options, 10 if you discount the 2 California emissions computers - which I don't care to purchase (truck isn't from Cali anyway)

Can anyone help me get to the bottom of this? I'd greatly appreciate it!

 

Hi,
I have been researching this for a 1995 4.9l with E4OD tranny. First does your truck have a MAF sensor and is it OBD II or EECIIV diagnostics?


Brian

 

Get the ID number from the original ECM and post it here.

 

Hi Brian,

I believe that it's OBD-1, not OBD-2. I do not know if there is a MAF sensor.

Sorry for the crap answers; I just haven't received the manual yet.

 

I'm going to dig into it tonight or tomorrow evening and, if I can't get it running, I'll remove the ECM and do so!

Thank you,

-Matt

 

Hi,
The way to tell if your engine is MAF is the air intake tube(s), if you have a two pipes going into a single pipe from the throttle body and there is a sensor in the tube (MAF) right before the air box or you have two separate tubes going all the way to the air box and no (MAF) sensor. The best way is to pull the original PCM as stated earlier, I was assuming yours had lost the numbers so you were not sure about it. I have a PCM from a 1995 4.9l manual no MAF so I could give you the ID off that if you have no other options.


Brian

 

So Brian, based on your description above, I'd have to say I have no MAF. From the airbox to the throttle body there are two distinct (molded together) tubes that attach to two small throttle body openings.

I'm actually fairly certain that the PCM would be the correct one for this truck...that said, when you state PCM is that different terminology for the ECM or are they different control modules?

Thanks man!

-Matt

 

Ok so I removed the PCM/ECM to check look for a burned board, but after looking at it, I don't see anything that really looks burned or even somewhat fried. Anyone else see anything that may look amiss? Is there a way to test this computer? I kind of doubt Autozone does it...

The number I got from Ford was: F3TZ-12A-650TB

The number on my current PCM is: F3TF-12A-650TB

Not exactly sure what the difference is, but I was able to find this one (A-1 CARDONE 785752 {#F3TF12A650TA, F3TF12A650TB, F3TZ12A650TA, F3TZ12A650TB} Reman. Engine Control Computer") on RockAuto, which has both of those numbers so I think I have found the correct one if I do indeed find out this is a bad PCM.

Here are the pics!

 

Marked with ID engineering number: F3TF-12A650-TB = Ford part number: F3TZ-12A650-TB / Obsolete ~ No Ford dealer or obsolete parts vendor has any.

Last MSRP: $294.92 / Dealer net cost: $191.70.

 

Thanks Number! I really appreciate you confirming it for me!

S/F,

-Matt

 

Hi,
Ford calls it a Power Control Module but everyone else calls it an Electronic Control Module so they mean the same thing. F3 means that it is a 1993 module which having a manual transmission opens up more years of modules to work as they do not need to also control the tranny. I am sure the one you found will work just fine if you need to replace it. If you need it, the one I have may have a different number but I do believe it starts F5 which means a 1995 module let me know. Your module does appear to be in very good condition visually it may not be the PCM, it could also be the distributor or the ICM there is a nice article on how to test which one of these may be bad just search for How To Test a Ford Ignition Control Module and it should come up with links to testing the other items I mentioned it is very detailed and easy to do.


Brian

 

Thanks BWD! I checked the ICM and it's working, but I do have yet to pull the dist cap to inspect that...if I don't get spark once I put a new battery in then I'll be pulling the cap to ensure it's spinning.

Does it make sense for my truck (a 1995 model) to have a ECM from a 93 model? Or could perhaps the previous owner have replaced the ECM/PCM/whatever anyone wants to call it with a different part and that could be what's causing the issue?

Well...now that I think about it, if that were the case then Ford wouldn't have given me the F3 number since they used my VIN to check it...

 

Matt,
I would think it being a 93 that is was changed at some point but at least you know that one works correctly UNLESS the guy you got it from changed it thinking it was the PCM and it was not. But I feel it should work fine in your truck. That is a good point about the Ford dealer giving you that number, there are so many versions of these things that really it seems NO ONE really knows exactly what all the differences are.
On these trucks the distributor puts out what is called a PIP signal which tells the ICM to fire the coil so if that is bad in the distributor that will also cause it to not start, that link I gave you also tells you how to diagnose this as well. So you need the distributor signal, the PCM and ICM to all be talking to make the engine fire as well as a good coil, wires, cap, rotor, and plugs of course, but those are the easy ones to replace and check for problems.


Brian

 

Thanks again Brian. With 280k miles on the clock and an unknown history, I can only guess what has and hasn't been replaced. Hell, this could be the 3rd engine for all I know.

Just for clarification though; I thought that the Crankshaft Position Sensor (I think Ford calls this the PIP) was mounted at the rear of the engine? But you are saying it's mounted in the distributor?

My buddy and his dad are both mechanics and they are going to help me go over it this weekend.

 

Brian you mentioned having the part number for a 1995 f150 300 I6 w/o MAF 5 speed manual. Can i get that mine in unreadable