5.0L General DiscussionThis section is for non-tech specific information pertaining to 5.0L Mustangs.
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So three years into it, it still needs an interior and some other odds and ends. I got it running... but it won't idle and I can't pull codes.
I started checking everything under the sun since I rewired about 85% of the car myself and thought I had screwed up somewhere along the line.
I couldn't find anything that I messed up, so today I got some time and pulled the ECU because I heard that if the wrong O2 harness and computer are used it can cause the circuit to fry and then not be able to pull codes.
Early in the build, I got an Ebay mass air conversion kit from Fiveology Racing that came with a used A9P computer... so I wanted to check it out incase the P/O had done something stupid with it and is causing me all this grief.
Well, once it was opened, it was obvious there was something wrong.
Can you see it??
Yep, it's a super small piece of jumper wire soldered from pin 46 to a transistor looking thing.
What idiot would do this and why? Pin 46 is the return signal from the diagnostic connector and most of the engine sensors... so this at least explains why I can't pull codes... and I hope it's the cause of the idle issue also.
I'm going to get a new ECU and see what happens... I hope what I've found has been the problem I've been searching for and I can finally get this thing running right once and for all.
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but glad to hear the car is still progressing, damn near thought you went the way of Rbarn and vanished into thin air... i remember his sweet twin turbo convertible
Nope, didn't vanish... just got close to completing it when I lost my job. I had to focus my attention on starting a new business for the past year and a half, but now I've been back out putting some decent time into the Capri again.
I'm gonna work on getting it done and then I'll post all the pics up on the original thread... so it WILL be finished and not become one of these projects that never gets done. I'll be sure to make some vids too.
This idle problem has been a major set back... I think of all the time I've spent trying to track down what has been causing it and it makes me sick. Since I built this car basically from scratch, I kept thinking it was something I did wrong and all this time my work was fine. Kinda glad to finally find the problem (if this jerry rigged ECU is indeed the problem) but mad that I wasted time second guessing MY work this whole time.
Old of course but I am interested to know if this fixed your idle/running issues as I am replacing my computer this week to fix a surge/running problem. I've gone through the whole checklist on idle/surge as well.
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