bloodyjaws

Hello all. Ok, I have some serious issues with my poor Z28. It's a 305/700r4 car. First off, the car was only driven a couple of times a month for several years. It developed an injector issue 2 years ago and had 1 bad injector and 1 that was shorting out, killing 1 bank. I put 2 new injectors in it and it seemd to run ok. I had the car shipped from Florida to Arkansas last year where it would run decent until I jumped on it, then it sounded lean. (Sucking air and falling on its nose). It would run good for awhile, then just run like crap. The car sat for awhile while I changed jobs...etc.
I figured out the cat was bad (glowing red after 5-10 minutes at idle.), and we put a test pipe in it. I replaced plugs, wires and the EGR (no vacuum). The car runs super rich at idle then falls on its face when trying to do anything else. It's hard to start at times and other times it barely turns and it's running. I've checked for vacuum leaks and done everything I can think of. I work with a guy who was a GM tech and he is helping with the car, but we are just about out of ideas. I don't know where else to look and the car is driving me crazy. Any help/ideas would be greatly appreciated.
Sorry for the long post.
Thanks, Jaws

bloodyjaws

Oh, I forgot. The car carries 42lbs of fuel pressure. It doesn't leak down. I'm not sure where to go from here. The car has black smoke from startup and strong fuel smell. It idles like it's on 7 cylinders but has spark to all 8 plugs. As revs come up it seems to struggle then just falls on it's face. The fuel pump is about 2 years old. Is there anymore information that I could give you guys? I really need help to get my car back on the road.
Jaws

8Mike9

Have him plug his scan tool in and take a look.

I've only worked on 1 rich running SD car, and had two things the issue, the O2 sensor was fouled badly...ECM was dumping in fuel to compensate-I don't think this is your issue, as you're blows fuel on start up (Open loop) ...

The Map sensor was bad, read proper voltage (I forget what now) before started...and stayed the same after the engine was on..

We put a vacuum pump to the MAP, it wouldn't hold vacuum.

I'm sure there are other things to look for, hope this helps.

bloodyjaws

Thanks Mike. I'd LOVE for him to hook up his scan tool. There are 2 problems with that. 1. The old scanner doesn't have a GM OBD1 adapter. 2. The new scanner (4 grand) decided it was a smoke machine 2 weeks after he got it and we are waiting on it's replacement.
I will check the o2 sensor and see how it looks. We are working on the car more or less on lunchtime only once or twice a week if we have room in the shop and a rack open. I'll have to check the MAP as well and see what it's doing.
I'm really hoping to get this thing at least drivable in the next couple of weeks. My wife and I took this car on our first date 18 years ago and our anniversary is coming up.
Jaws

bloodyjaws

UPDATE. A couple of weeks ago the car started doing an odd thing. When it was cool in the morning the car would start on the first crank and sound pretty good. It would idle ok but stumbled at higher RPM. At noon, when it was much warmer, the car wouldn't start at all. If it did start it was missing, running rich.
I ordered a new computer for it and swapped the chip. Now the car barley runs and will barley idle across the parking lot. You can't even think about giving it gas...stumbles horribly and tries to die. The old computer was so hot after driving across the parking lot that you could hardly touch it. (15-20 seconds tops)
Any ideas on what to do next? I'm getting really frustrated with it.
Thanks, Jaws