mdelorie Posted July 15, 2007 Report Share Posted July 15, 2007 I want to reset my PCM without disconnecting my battery - I can just pull the fuse for a few minutes, yes? Quote Link to comment Share on other sites More sharing options...
birdman Posted July 15, 2007 Report Share Posted July 15, 2007 yes Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 15, 2007 Author Report Share Posted July 15, 2007 and then, an idle re-learn is basically just starting it up, letting it idle for 10? minutes and shifting it through the gear selection? Quote Link to comment Share on other sites More sharing options...
birdman Posted July 15, 2007 Report Share Posted July 15, 2007 just put it in drive and sit there for a few min and ur good. Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 16, 2007 Author Report Share Posted July 16, 2007 Alright, so, here's the background on why I was wanting to reset my ECM: Yesterday I started driving it only to notice that the speedometer and cruise control were dead. As well, it started idling very high (2000 RPM) and missing a bit. It did this intermittently for yesterday and today. Today I went to pull codes from the ECM to investigate the problem, and I pulled a 55. After 55 flashed up, the ECM went dead completely. It won't go into diagnostic mode now, and the engine won't start. Cranks no problem, won't pick up though. According to my Haynes manual, code 55 is an ECM problem; they recommend checking the ECM grounds and reseating the PROM or MEM-CAL. I'm about to try that now. So, my questions are: Has anyone else run into this issue? Is it more often a problem with the MEM-CAL or the ECM itself? Which part is cheaper? Which part number do I need if I need an ECM (or where can I find the part number on the existing one? Which one should I try first? MEM-CAL or ECM? If it's the MEM-CAL, I might as well get a performance chip to replace it - who's got a decent chip with good fuel economy? (one of my primary concerns) Where are the grounding points for the ECM? Is it grounded through it's own little bracket / chassis, or is it through a wire? Sorry for the long list of questions. Thanks guys. Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 16, 2007 Author Report Share Posted July 16, 2007 I pulled the ECM, cleaned it up, reseated the MEM-CAL and now it's running. It's consistently providing a code 51 which is a MEM-CAL problem, so I think I'll start there. I was looking at the 60degreev6.com performance chip, and it looks like a pretty nice setup - anyone running one? How was fuel economy affected? Quote Link to comment Share on other sites More sharing options...
birdman Posted July 16, 2007 Report Share Posted July 16, 2007 well i have the 60* chip but that wont solve your problem because its actually an adapter that you have to plug your stock chip into also, if your stock chip is bad it wont do you any good. just go to a local yard and pull a whole new ecm, they usually run less than 30 bucks. Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 16, 2007 Author Report Share Posted July 16, 2007 Yeah, I called the local guy today. Said he'd give me one (an entire ECM) for 50 bucks, when they usually run for 100. The local guy is also notoriously expensive, so, I'll take it anyways. How did you find your fuel economy after plugging in the 60* chip? Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 17, 2007 Author Report Share Posted July 17, 2007 I picked up an ECM for an 88 Grand Prix 2.8. The SRV number is identical, but the BCC code for the MEM-CAL is different. I believe you can swap MEM-CALs regardless of this code, is this correct? Would a MEM-CAL from 88 for a 2.8 be more primative than one for a 91 3.1? Quote Link to comment Share on other sites More sharing options...
ManicMechanic Posted July 17, 2007 Report Share Posted July 17, 2007 I imagine you'll run too lean for a 3.1 using the 2.8 MEM-CAL, alas the 1988s had a MAF sensor as well. Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 17, 2007 Author Report Share Posted July 17, 2007 Yeah, it's idling terribly. I haven't driven it yet, but the A/C doesn't come on. I'll try swapping MEM-CALs, but my old ECM was pulling a code 51 for a MEM-CAL error anyways, so I'm not overly optimistic. I'll just take it back and tell the guy it doesn't work. Quote Link to comment Share on other sites More sharing options...
mdelorie Posted July 17, 2007 Author Report Share Posted July 17, 2007 So, the engine idles normally with an AUSJ 3.1 MEM-CAL in the old 2.8 ECM - and the air conditioning works. Does anyone know if it's possible for a faulty ECM to report a MEM-CAL error? Quote Link to comment Share on other sites More sharing options...
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