ZeroDCX Posted November 6, 2012 Report Share Posted November 6, 2012 (edited) Okay, I've got a 92' Buick Regal that sat for a couple months. Before sitting, it was fine engine-wise. When I came to start it up, it idles like crap, the brake and low coolant lights come on (even-though the parking brake is not set and the coolant level is fine) also the Check Engine light blinks like crazy... Almost as if it's in diagnostic mode. Also the passenger fan comes on at low speed. It idles high with a miss every now and then. It won't die and I can freely rev the car with no hesitation (though I did not attempt to really get into revving it since something's apparently wrong with it). Cliff notes: - Car idles high and misses - Brake and Low Coolant warning lights stay on - SES light blinks constantly while running, even-though diagnostic port is not grounded - Passenger side cooling fan stays on at low speed during operation - Only codes I pulled from it is the (12), 21, 23 Also to note, before parking it I pulled these codes (almost a year ago): (12), 22, 26, 34, 39, 41 The battery has been replaced today. I'm also going to fill with "fresh" gasoline, replace the fuel filter, plugs and wires along with getting the alternator tested. Any suggestions? Edited November 6, 2012 by ZeroDCX Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted November 6, 2012 Report Share Posted November 6, 2012 21 = TPS voltage high 23 = IAT low as for the other ones, if they pop up again.... 22 = TPS voltage low 26 = Quad driver A issue 34 = MAF failure/low signal 39 = TCC (specifically that the TCC has been detected as non-functional) 41 = cam sensor either you have a really flaky electrical system, or the ECM might be your issue. with all of those popping up, it has to be a common cause. high idle is probably caused by the TPS DTC being set. Quote Link to comment Share on other sites More sharing options...
ZeroDCX Posted November 7, 2012 Author Report Share Posted November 7, 2012 Seems as if you're on the right track. If I turn the ignition on without starting. The passenger side fan, will turn on and off repeatedly, the iac starts moving sporadically along with the check engine light doing blinking like crazy. New plugs, wires and got my alternator tested. I'm going to start down the long road of examining the harness for frayed wires, shorts and bad connections... sigh. Thanks for the reply. Quote Link to comment Share on other sites More sharing options...
Penglii Posted November 7, 2012 Report Share Posted November 7, 2012 If you can get a good junkyard ECM for cheap (or even borrow the ECM from someone you know with a compatible car?), that is potentially an easier place to start than checking the wiring harness for faults. If it still flakes out with a known good ECM then it's probably a harness problem. Quote Link to comment Share on other sites More sharing options...
White93z34 Posted November 7, 2012 Report Share Posted November 7, 2012 double check things like grounds, aux terminal connections, evidence of animals chewing on wires too. Quote Link to comment Share on other sites More sharing options...
ZeroDCX Posted November 7, 2012 Author Report Share Posted November 7, 2012 I'm going to pick up a ECM from the junkyard today for $50 and try that. I did however find some acorn shells in various places of the car, so I can only assume some squirrels were inhabiting the car and chewed some stuff. Thanks guys. Quote Link to comment Share on other sites More sharing options...
skitchin Posted November 7, 2012 Report Share Posted November 7, 2012 Eek, sounds like a case of the squirrels or chipmunks. ECM could well be bad by this point, but might just be a gnawed harness to blame. Quote Link to comment Share on other sites More sharing options...
ZeroDCX Posted November 7, 2012 Author Report Share Posted November 7, 2012 Update: So I just returned from the junkyard with a spare ECM and made sure to get an ECM with the same SERV. NO. Slapped it in the car and it fired right up. Idling fine and all is well. I assume the stock ECM shorted out some how. But I will still go over the harness just to be on the side of safety. Thanks for all of your help guys. Quote Link to comment Share on other sites More sharing options...
Penglii Posted November 7, 2012 Report Share Posted November 7, 2012 Glad to hear that solved the problems Quote Link to comment Share on other sites More sharing options...
ZeroDCX Posted November 7, 2012 Author Report Share Posted November 7, 2012 For future reference concerning anyone that has similar problems and attempts to diagnose themselves. Symptoms (with ignition on/engine off and engine on): - Passenger Side Fan cutting on and off repeatedly - IAC rapidly opening and closing - AC Compressor kicking on and off repeatedly - High Idle with a miss - Rapidly Blinking SES light - DTCs 21, 22, 23, 26, 34, 39, 41 (if you can manage to pull them in diagnostic mode) Resolved by replacing ECM. Thanks again guys. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted November 7, 2012 Report Share Posted November 7, 2012 did you transfer your existing MEMCAL into it, or use one that came from the junkyard? Quote Link to comment Share on other sites More sharing options...
ZeroDCX Posted November 7, 2012 Author Report Share Posted November 7, 2012 I used the MEMCAL from the junkyard. I made sure the SERVO. NO. on the replacement ECM was the same before doing the swap. It also came from a 3.8L Buick Regal. Should I have transferred the stock MEMCAL to the replacement ECM? Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted November 8, 2012 Report Share Posted November 8, 2012 if for nothing else, to determine if it was the ECM or the MEMCAL itself was the problem, yes. otherwise, there were calibration differences through the years for the 3800 regals, you may find odd behavior with the junkyard unit if it isn't a 100% compatible MEMCAL. Quote Link to comment Share on other sites More sharing options...
mra32 Posted November 8, 2012 Report Share Posted November 8, 2012 as soon as i read this, i almost knew it was a bad ecm. Ive been through it myself. Good to hear you got it sorted Quote Link to comment Share on other sites More sharing options...
ZeroDCX Posted November 9, 2012 Author Report Share Posted November 9, 2012 if for nothing else, to determine if it was the ECM or the MEMCAL itself was the problem, yes. otherwise, there were calibration differences through the years for the 3800 regals, you may find odd behavior with the junkyard unit if it isn't a 100% compatible MEMCAL. If the MEMCAL was indeed the problem and not the ECM, then couldn't that cause potential issues for the replacement ECM if I swap them? as soon as i read this, i almost knew it was a bad ecm. Ive been through it myself. Good to hear you got it sorted Thanks man. I can't complain though. For a 20 year old car, she's not given me too much trouble as mush as I've beat on her (except the fact that she like chewing through Crankshaft Position Sensors). I actually read through your previous thread which gave me the idea along with the other guys who posted in this thread to look into the ECM. So yeah, I really should be thanking you too! Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted November 9, 2012 Report Share Posted November 9, 2012 only temporarily. if it does cause issues(and is at least one problem), swap the other one back in. if it works correctly with the old one in it, that's the final factor for the ECM being the culprit. Quote Link to comment Share on other sites More sharing options...
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