Possible PCM Failure
#1
Possible PCM Failure
A coupld of days ago my '95 F15 4.9L started but ran very rough. I turned it off, tried it again with same result. I had to wait til the next day to try it agin and it ran fine. Today, it will not start. I noticed that the fuel pumps ( I tried both tanks) continued to run with the KOEO condition.I have good spark, fuel in both tanks, the fuel filter is two months old. Threads here indicate a bad PCM but there doesn't seem to be any positive way to trouble shoot the problem beyond the fuel pump continuing to run rather than time out. I would rather not start changing expensive parts as a troubleshooting method.
I would greatly appreciate any advice.
Thanks in advance.
I would greatly appreciate any advice.
Thanks in advance.
#4
Sounds like the injectors have quit firing also now. Take the PCM Computer out and open it up. You should be able to see what is wrong in the area around the electrolytic capacitors in it.
Some posters have replaced the electrolytic capacitors if nothing else looks burned up and that fixed it.
If you send it off that is about the only thing that gets done (electrolytic capacitors replaced) by the repair places that fixes them.
That is why they do not always work like they should when you get a rebuilt one from an auto parts store as it was something else wrong with it other than the filter caps.
Some posters have replaced the electrolytic capacitors if nothing else looks burned up and that fixed it.
If you send it off that is about the only thing that gets done (electrolytic capacitors replaced) by the repair places that fixes them.
That is why they do not always work like they should when you get a rebuilt one from an auto parts store as it was something else wrong with it other than the filter caps.
#5
I will get a new unit but I am having a problem identifying the component. I saw in a photo that it is on the firewall under the left hood hinge. There are two devices ther annd the one outboard closest to the fender well was indicated as the PCM. I opened that and it appears to be only a bulkhead connector. I intend to open the other device now to what is there.
Thanks to all for the help.
Thanks to all for the help.
#7
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#8
#9
Thanks to all. I have it out-now to find a reliable replacement. i have two options, O'Reilly or an independent company that can exchange mine for a re-conditioned one. Dont have price on either, but have to get it.
Again, I wish to thank all of you for your help. Could not have done it without you.
Again, I wish to thank all of you for your help. Could not have done it without you.
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