Hi guys (and gals),

I am a long time reader but seldom poster...

I am having some problems with my '94 Z28. It has about 240k on the body, the crate LT1 was put in around 180k (so it has about 60k on it for those that are bad at math). I think everything is pretty much stock except for the rims and the exhaust. I am the third owner and it has been my daily driver for almost 3 years now.

I started having some problems starting it this summer when it was really hot outside. The battery was 7 or 8 years old and was not holding up under load, so I put a new one in and that fixed it but something still didn't seem quite right. Well, about two weeks ago, I went out to my car after work and tried to start it. I stuck the key in and tried to crank it and as soon as the key went from ON to Start all the gauges and lights went out and the engine didn't do anything. I tried to crank it a few more times with the same result. On the next try I jiggled the key some and the car started, but it started hard and was running really rough, like only one side of the engine was firing (the car was moving side to side a little). I pressed the accelerator some and that made the engine almost quit (like it was getting starved of fuel). So I shut it off and tried to start it a few more times and would either have everything shut off or if I could get it to turn over it wouldn't start.

I had it towed to a shop (which has an excellent reputation) so they could diagnose it for me (I am not that good at diagnosing problems but I can fix most of them if I know what they are and if the directions are in the Haynes manual ). They were closed by the time my car got there, well they called me at work the next morning and said my car started right up and was running really good and the engine sounded real strong etc... They messed with it some more to see if they could get it to stop working again, but to no avail. So, I got dropped off at the shop after work and it started right up and I headed home.

I got about two miles down the road and was sitting at a stoplight, it turned green and I pressed on the accelerator and the engine bogged down and quit. I tried to start it again and it would turn over but not start. I did get it started once and it died as soon as I pressed on the accelerator. I thought I had run out of gas since it was low when it went into the shop and they had driven it around some. I got a couple gallons of gas and put it in the car and it started doing the whole ON->Start all gauges/lights turning off and nothing from the engine thing again. So, I called the shop and the owner and another mechanic drove over to the parking lot. They did some troubleshooting there and said the fuel pump was not turning on when I turned the key to ON. So, they had it towed back to the shop.

During their diagnostics the next day, my car started running fine and they could not get it to stop working again, but the owner said he was 95% sure it was the fuel pump or something with the wires with what diagnostics they were able to do. They quoted me about $740 for them to fix it (which from what I have read is about normal). My dad has worked on cars most of his life and was going to be in town for Christmas and said he would help me do it. So, I had it towed home even though it ran fine at the shop and ran fine when they took it out. My dad did some troubleshooting when he got here and the fuel pump relay was not putting out the proper voltage and the fuel filter was in desperate need of changing. We changed those and worked on some other things (bushings, ball joints... non electronic things).

I finished up the tie rod ends today and was going to take it out for a drive around the neighborhood since it finally quit raining (in case I had to push it home). It didn't start. It would turn over once and then quit (all gauges/lights would go off and nothing from the engine). I jiggled the key some and it started right up, and idled fine and was fine when I would rev it up some. Or so I thought... I then noticed that the battery voltage gauge was being weird. It would jump up a couple volts and then go back to normal, then drop a couple volts and go back to normal. One time it dipped down into the orange range on the gauge and the engine sounded like it was about to quit but then the voltage went back up to normal and the engine evened out again.

So, I am thinking it is a problem with the voltage regulator in the alternator combined with the ignition switch going bad/shorting out. Any thoughts or other ideas?


(wow, that was long... sorry for the length)

 

Its sounds like your ignition switch is burned up.I think Shoebox has it on his site.

 

That would have been my guess. I would replace those two things, then have your battery checked out at Autozone or something to make sure it has a full charge, then take it from there.

 

Thanks for the quick replies!

The first paragraph here is exactly what I've been seeing.

Is the voltage regulator external to the alternator? I didn't see it in the manual or on shoebox's site.

 

The voltage regulator is internal to the alternator.

 

for search sake...

I found a couple of videos on youtube of how rebuild or repair an alternator and the guy actually uses a GM CS144 alternator which is found in 4th gen 93-97 camaros.

Part 1: http://www.youtube.com/watch?v=LdFA6WF8lVg

Part 2: http://www.youtube.com/watch?v=vKbX7mezuFM&feature=user