Stalls only when accel hard from stop
 

New guy here. I hope you can help me out. I searched the threads and couldn't find someone with the same problem. I have '99 S10 4.3L. Extreme I have just changed the head gasket, intake manifold gasket, and exhaust manifold gasket along with new plugs. It was a heroric amount of work and when Istarted the engine all seemed perfect. Smooth idle, no weird sounds. When I drove it, it stalled when I pressed the accelerator. If I gently push the accelerator it runs fine, then when up to speed, 5mph or more it runs regardless of how aggressively I push the gas. Only when back at a stop, if I push the accelerator with any urgency it will stall. I assume a vacuum problem? One more thing, the SES light is now on, it wasn't before. Any ideas anyone?

RE: Stalls only when accel hard from stop
 

The SES light is on for a reason. Have the codes checked and let us know what the actual codes are (Pxxxx). This will help to greatly narrow the problem down.

What happened that prompted you to change out the head gaskets?

RE: Stalls only when accel hard from stop
 

I just changed the intake manifold gasket on my 2000 blazer and I have the exact same problem. The SES light is on and it does EXACTLY what yours is doing. I went to autozone to have the code read, and it said it was a faulty crankshaft sensor. The manager practically guaranteed my timing was off and that I had inserted my distributor wrong by one tooth. I'm going to take it into a shop. For those of you who have had a timing job done, what is the average cost orwhat should I expect to pay (ballpark) ? Thanks. Oh, and swartlkk knows his stuff.