This is gonna be kinda long...but descriptive..

Just finished the resto of my 89 GTA, LB9, T-5. Was running great until about a week ago. Just seemed that it was lacking the power it once had and had developed a miss at about 3K RPM. Today, after driving about 60 miles, she started to heat up. Hit about 240 in traffic before I could get moving again. I know that the original fan switches kicked on at 228, so 240 is not bad per original standards, but I have run a Hypertech 180 switch for 3 years now and the car usually sits on 190. Got home and neither of the fans work, even with AC blowing. I got on here and found some troubleshooting methods, I found the relays, orange is the "hot" wire, black/red is the fan wire. Had power on the Orange, so I jumped the fan wire direct to orange and nothing. Then the orange wire had no power...Funny thing is, is that power came back on in a couple of minutes, tried one fan at a time and finally lost all power to the orange. Checked all fuses and links and all are OK. Now car is sitting in the driveway and will crank but not start. I do not hear the fuel pump kick on. Could my ECM be dead? It is a reman unit. Is there a simple test I can do? Any ideas and help is much appreciated

 

to test the ecm, turn the key to on position, does the engine check lite stay lit. if not, then ya your ecm or prom is fryed.thats tight you hace the hypertech switch, did you get the thermostat. if its hovering around 240 thats decent i guess. but with the switch and themostat added its usually best if the prom be replaced with a hypertech thermomaster. if your fuel pump is acting up one way to check it is turn the key to on, press the schrader valve to see if fuel sqruits out, it doen then youre okay. but if not the pump, or the pumps check valve is bad., if youre getting fuel but no start, try check the coil in the dizzy. report back if you have any engine code thrown at you., you can test the computer code list by ground the a and B dianostic plug by your knees while in the drivers seat. count the codes, and report back

 

Thanks dudeman...just noticed the fuel pump when she wouldn't start. I believe the ECM triggers the fuel pump to turn on. If its fried, it may not be doing this. I have a FP guage set and its set at 49lbs via a BBK AFPR. I will check later to see if the SES light stays on. Would all this irratic behavior be related to a failing ECM? I did get a code 14 today when she heated up. and I do have the 180 thermostat with the switch...best thing I ever did to the car

 

i dont got my book in front of me, but from what i read, a code 14 is overheating. try uplugging the power terminal to the batt, thats how i reset codes, then if she starts up itd be on a default fuel mapping open loop until the o2 senor hits 600f* then the car will go into closed loop mode and be reading off all sensors. um if the engine light doesnt stay lit by just turning to the on position with the key then ya, the chip maybe fryd. but if you dont hear the pump going to can test it by applying power 12volts to the G terminal. and even if then you dont hear it, then ya the pump should need looking at, but you said pressure is high, so next would be to look at the dizzy, maybe got loose and moved too advanced to start the car, check to see if the diizy hold down bolt is loose., next see if you get power to the dizzy nexy pull the spark plug wire from the plug and put it next to a ground metal like the alternator bracket, if when you turn over the engine and you dont see spark then the coil/ dizzy is to blame. report back

 

I dont think its in the diz...I'm thinking my comp is toast. you can also reset your codes by disconnecting the small fuse link near the batt feeding the ECM, did that and it still ran until I crossed the fan and power wires and disconnected and reconnected the ECM wiring..after that, no start...thinking this killed the comp.
BTW--fuel pump should be fine...its fairly new. I think its just that friggin computer

 

if youre getting codes from the computer, then its not the computer

 

I got the codes before it died...BUT, this morning she started up....Still no fans running though....thoughts

 

try going into diagnostic mode.. if when you ground the a and b terminals and you dont hear the fans on, but your computer engine light is flashing, then is your fan relay. but if your not getting any flashing, then the prom is shot.

 

thanks man...will try in a few...I think I should have two fans relays...right? Both appear to be up near the air filter

 

Burnt fusable link...just couldn't see if without the batt removed. Installed 25A inline ATC fuse and all is good.