6 months ago, bought 88 LSC with 70K milesin nice shape for $2000.00. Car was running great , but suddenly one morning began stalling after cold startup, would rev up after starting as normal and then drop to stall.

Mechanic found and fixed something in the distributor which he said sends a pulse to the fuel injectors which got it to idle OK, but it still lacked its normal power. Few days later got progressively worse, would barely accelerate and was blowing alot of blue and black smoke.

Subsequent "diagnosis" spit out about 20 codes and " mechanic" could not reconcile, and after several attempts gave up saying it a "computer issue".

I Dont want to spend 3 grand for a dealer to guess this out and replace everything on a 2 grand car, but want it fixed. Anybody out there relate similar experience and/or probable cause and fix? We can do mechanical stuff, but have no experience in deep EFI analysis.

Similar symptoms had happened on my lightning after two things happened.

1. Exhaust leak was getting worse. Turned out to be the air lines from the smog pump to the exhaust were rusted. Plugged these lines.

Instantly started running a few codes and black smoke, rough idle, surging idle, and little or no power.

Removed smog pump, plugged air lines to the rear of the heads, and replaced the o2 sensor.

Codes went away, power was back, and vroom.

Note: I also replaced both of my fuel pumps and both gas caps at the same time. maybe nothing related.

Thanks for the info. We'll look at that. My son had a stereo installed in the car about two days before all this began. I know they bypassed the amp with an adaptor, but I cant help wondering if anything they did in the dash or the rear deck might have had an effect. Any possibility at all? Like from arcing a power feed or misconncecting any jumpers etc. Of course they (the stereo shop) say no way.

When is it blowing this smoke? Is it only on start up, only when you shift, only when you are idling?

Pull codes, and let us know what they are.

Smokes when trying to accelerate, or revving in neutral . Clearly running very rich. Barely idles.

We have to go get the codes. Could be a few days.

Is the vacuum line hooked up to the MAP sensor on the firewall?

for the stereo u should have went XL motorsports, they would have taken care of u good,
And for the engine they when have solve that to with their service dept.
Try the out never to late. things to check and do map sensor clean egr,vacuum leaks

www.xlmotorsports.net