Andrew6.688

My 1994 LT1 trans am A4 has been having problems lately, and I'm not sure what to do. I'll explain the situation

1) about 2 weeks ago i ran out of fuel, gauge said 1/4 tank.
I refilled the car, drove home about 4 miles fine.

2) the next day it started up fine, drove about 5 miles. about an hour later I go to start it up, no go. it turns over, but wont start. i rolled the car to a level surface and it started about 25 minutes later.

3) changed that fuel filter, added lucas oil fuel system cleaner. car starts fine, drove to movies that night, about 25 miles in total. on the way home i gunned it and it did misfire 2 times at WOT

4) the next day i drive about 1 mile and it dies at the top of a big hill, while driving. just total loss of power. engine dies and i just put it in park. about 30 minutes later it finally springs to life, but dies about 1/4 the way home. about 20 minutes later it starts again, and gets 90% of the way home, engine cuts out again. i coasted towards my house at about 30 miles per hour with no power brakes or steering and into my driveway, frightening.

5) next morning i start it up without a fuss, take it about 4 miles to o'rileys, they couldnt help (No codes, and the guys there didnt know what was up). So i take it about 3 more miles to my mechanic, no fuss. he tested it for 3 days. injectors are good, fuel pump was around 30 psi, alternator wasn't in the best shape, but he couldn't find one problem that would kill the car in the road. we figured under load the fuel pump might not have enough pressure.

6) new ICM and new fuel pump are installed. AC delco ICM and racetronix kit fuel pump.
she starts up asap, good as new. drove her around for about 45 minutes, top off my tank, drive about 10 more miles around my town. never had driven better.

7) Next morning i took it out to a friends graduation party, no fuss. at the party i show it off to a few older guys, repark it.
about 30 minutes later i go to leave. and nothing. keeps trying to crank, but no such luck. about 15 minutes later it starts and i get home, but it felt very sluggish, felt like it was dragging, not quite sure how to describe it.


8) check my battery, its at 25% according to my tender, and wal mart and orileys both say its a good battery, even if its from 10/08.

9) charger the battery, starts perfectly. drive it to a friends. 3 miles, seems to drive fine. 30 minutes later i go to leave, no go. just keeps whining, but never seems to start. a few minutes later it reluctantly starts, and drives home fine, although felt like it might have been a bit sluggish under hard throttle.

10) the charger claims the battery is fully charged, and I'm not sure whats up.

my mechanic said he was full today, soonest he can get to it is tomorrow, so until then I'm looking for help from experienced lt1 guys.

Thanks very much!

Transmarrowbird94

Crank sensor going bad? I had a grand prix come in once that did something very similar to that and swapped out the crank sensor and that fixed the problem

matt94z

iTrader: (49)

My car did that about 10 years ago and it turned out to be my Opti. My car would just shut down while driving and wouldn't restart for sometimes up to an hour....

englundjd

i think you should try a new battery, people have had trouble with bad batteries in these cars before, if that doesnt help you should verify that your fuel pump is working correctly, at idle it should be around 40 psi and i should go to the mid 40's at wot

Andrew6.688

alright, ill test the fuel pressure, i could have fouled up the pump install for all i know

Quazz

iTrader: (1)

Wiggle your coil harness and Opti harness at idle. I had the same issue with my 94 camaro A4 TWICE. Once was the opti harness, once was the coil harnesses. If you tugged on either, they would kill the car. The opti threw a code when the harness was flaky, but the coil connectors did not. Worth a try!

Andrew6.688

Well thats the easiest way to try and test it ive heard, thanks!

Update. It only seems to be when the car is started that it has a problem, once shes off there seems to be nothing stopping her anymore. today i drove it about 10 miles, after about 30 minutes i left and got some food with the girlfriend. the car gave no fuss on startup, but we went to a drive thru to avoid possible complications. after probably 5 hours or so i left. the car hesitated and almost started its near endless cycle of turning over without starting, but it caught at the last second. if that makes sense, I'm fairly new to the whole automotive scene

1965GP

iTrader: (2)

Had the same problem on our 94 TA- ended up splicing in the opti- MSD harness was not making good connection with factory harness. Took forever to finally find it

Andrew6.688

i just put a new opti + harness, new plugs and wires, a new waterpump, and battery.

it starts up fine now, and its a biiiiit quicker now

but sometimes the starter goes for a bit (2 seconds) before it will start up, and before it was always an instant start, no matter what.

any thoughts?