i took my 97 f150 (4.6L, 166,500 miles) into the shop today because it was misfiring. They said the ecu is randomly shutting down cylinders on me, but i'd have to take it to a ford service shop to get the ecu checked. ford said it'd be $600 for a new ecu! has anyone had this problem? and how hard is it to change out the ecu, and is there any special equipment or calibration involved?

thanks,

Brian

 

Hey Brian.
Have the spark plugs been replaced, or the spark plug wires? You can have the codes checked by a parts store for no cost, (most). You might try clearing the codes, and soon as the check engine light comes on have it checked asap. Let us know what the codes are. I have not seen many computer or ECU, OR PCM'S go bad. We have a few 97's with over 267k miles on the clock and still going. I think there is a run safe mode that will kill cylinders in the event of an overheat condition so the dead cylinders will act like a air pump to cool the motor. Racer Guy could tell you more about this. My bet would be the plugs or wires. Good Luck.

Dave P.

 

plugs and wires were replaced 4 months ago. goodyear service center ran the codes and told me it was ecu related, but didn't have the equipment to "flash" the ecu. they said both coil packs were shutting down cylinders at different times.

 

Like bosshoss said it's extremely rare that a PCM dies on one of these trucks.
I think I'd take it to your dealer and have it diagnosed before I bought anything.
If you're worried about the cost at the dealer you can tell them that if they haven't got it figured out in say 1 or 2 hours to just stop and let you know that it will be longer. That way they won't spend tooo much of your money checking it.
If you don't want to get your dealer to look at it then post the codes and someone here can probably help. The description of what the code means isn't always totally accurate so if you post the code we can look it up and maybe help.

 

thanks for all the advice.....turns out the pcm was fine (just like everyone said it would be), ford said the #3 cylinder wire and plug were bad. I don't know why goodyear thought it was the ecu, but replacing that wire fixed the problem. After i got it home i went ahead and replaced the rest of the wires with motorcraft wires. The bosch wires that were in it before were only 4 months old, but ford told me that they have found that only motorcraft wires hold up. Guess I learned my lesson with wires......only use motorcraft!
thanks again everyone!