Recently my car with a 350 TPI, AT and 6E Prom started stalling while coasting in drive mode. It starts right back up but doesn't want to maintain an idle with the tranny in drive. This car has headers, 24 PSI Accell Injectors, Edelbrock aluminum heads and an adjustable fuel regulator. A check of the service code gives the ECM as the source of the trouble. After reset, the same things seems to happen on rainy or damp days. A coil was changed in here but other than that, nothing has been done to ignition. I'm wondering if the trouble is in the ignition module of the distributor, a short in the PROM or fuel pressure problems.

Aloha,
Laser

 

The service code might be helpful.

 

Friend, right, it is a 42. Ignition circuit shorting or fuel pump relay shorting is what the book says. I'll make an appointment and get to the bottom of it shortly.
Happy Holidays,
Laser

 

The codes should be the same for both of our cars.
Alldata shows Electronic Spark Timing (EST) error for code 42.
The fuel pump error code is 54.

 

Keep Your GM Car all GM!, What seems to have been the problem was a scoured and cracked rotor. I had replaced the rotor and cap about a year previously during another repair episode. As it turns out this Gold Plated Special was made in China. Needless to say, the rotor didn't hold up and occassionally caused the engine to stall at low idle speeds. There is carbon arcing all over the contact element and a slight crack running down the stem. It would re-start initially until it failed completely blocking any spark from the cylinders.
Hope this helps,
Laser