I have a 95 z28, pretty much stock except cold air intake and cat back exhaust. It is an auto with about 150k on it. The car never has been a real powerhouse. It is a convertible, and I had a new top put on it over the winter. Since I have gotten it back it has an intermediate shut off of the lt1. It doesn't matter if its been running for 2 hours or 1 minute, it will just shut off randomly. I don't lose any power from the battery, after it shuts off it sounds like its not getting any gas. Usually it will refire after about 10 minutes, but before it refires the air pump makes a spinning noise. If the air pump doesn't make that noise it won't start again. I have replaced the fuel pump, fuel relay, tps, coil, cleaned the maf and have taken it to many garages including the local chevy dealer and no one knows what is wrong with it. It doesn't show any codes on the dash and I was told that it wasn't throwing any codes on the garages computers either. I was told by some people that it might be a crank positioning sensor, which I think is on the opti. I replaced the opti and water pump last year. This has to be the biggest POS that I have ever owned. I have also replaced the O2 sensors and the coolant sensor. The other thing that I thought of was the vats system, but the security light doesn't come on when it quits. HELP!!!!!!!!

 

I also have replaced the icm with no difference.

 

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