My son just recently purchased a 2001 blazer. We have replaced the spider injectors the map maf tps iac sensors the ditributor cap and rotor fuel pump and fuel filter spark plugs and wires. We finally got 60 psi in fuel pressure. It runs ok when in park but when you put it into gear it sounds like it is missing and wants to stall. As long as you give it fuel it drives nice. what do we need to do to get it to idle correctly in gear? Any ideas?

 

Distributor Timing correct? How does it idle, Check Engine light or no? Check at night while running for jumping sparks, even if the wires were replaced. Also check for vacuum leaks again at night by using a can of carb cleaner sprayed into the engine bay from a good distance with a light shining on it to watch if particles get sucked into any one place.

 

We checked no vacuum leaks. Yes check engine light is on we get code 300. However when we take off egr valve the idle went over 1000 however when you rev the engine the idle seems to stick to high then starts to lower. I feel bad for him. It was only supposed to be a simple tune up. He is now over 800 in the hole with this truck. That we are going to check next is the timing... I thank you for your replies...

 

having an open EGR port would cause a vac leak i believe, Tried replacing the valve or using a blockoff plate?