engine possible misfire but no code, rough idle, stalls
 

Hello every body. I have used this forum many times for help with my 1995 blazer 4.3l but now i cant really find anything specific to my issue. My blazer won't start without starting fluid, it tries but never quite gets there. It also has a rough idle (bounces between 500 to 900rpm) when i shift into any gear it immediately wants to stall and unless my foot is on the gas it does. there is also detonation when I hit the gas. Here's what i have replace so far:

New Platinum plugs
new wires
fuel pump and filter(previous problem)
Ignition Control Module
Head gaskets
upper intake gasket
Cleaned EGR, Idle control valve

only codes that pulled up were ignition control module fault and engine coolant temp sensor.

PLEASE HELP! I'm thinking possibly a new EGR Valve?

Are all connections correct? I replaced my head gasket and i had similar issues but not as bad. My problem was one of the connections were plugged in but backwards. It had recently busted so i had a 50% chance of getting it right. i let a mechanic look at it and he disconnected the cable, flipped it, then plugged it back in. I wish i remembered what the cable was called but it was to the left of the throttle body.

Check the connector that plugs into your fuel injector. Mine was loose and I got it tightened up and had no more problems with it.

Even though you previously replaced your fuel pump, I would do a fuel leakdown test. Especially if the pump you used is not a Delco or Delphi. Even if it is, I would still do the leakdown test. If it's firing with starter fluid, that makes me think it is a fuel delivery issue. However, a weak spark (orange instead of blue) could cause the problem also. Are the wires you used AC Delco? How about the cap and rotor? Either way, I would start with the fuel leakdown test.

EDIT: Key ON, engine off, fuel pump activated, pressure must be 55psi to 61psi. It must remain above 50psi for at least 10 minutes after the pump shuts off. Check it out and post your results.

EDIT II: Also, is the CEL on?

had same/.similar problem, try cleaning your MAF sensor ( mass air flow ) its on your air intake hose ( pewter looking metal unit ) with MAF cleaner, PS BE CAREFUL NOT to break filaments. good luck

fuel pressure is good, 58 psi and holds steady at 53psi for the leak down check. The CEL is on, it was flashing until i changed the gaskets now it stays on steady. I'm assuming because i havent cleared the code since i changed the ICM and temp sensor. I ran premium gas and the performance improved slightly(it longer tries to stall when idling). I'm getting a new spider injector and fuel pressure regulator tomorrow.

Since only the #1 spark plug had carbon build up on it i'm assuming that is the problem cylinder.

a new issue has come up. Now the motor is "tapping" through the full RPM range and the dash oil pressure gauge hover between 20 and 40. There is no oil leak and the exhaust is clean although still smells like gas because of the misfire issue. This just happened today after driving about 5 miles down the road. Did my oil pump suddenly die? Im running castrol high milage 5w30 and a fram oil filter. just changed the oil 2 weeks ago.

The oil does not smell like gas and the coolant is clean and oil free.

Hey Tony1987mustang, did you ever figure out this issue with the stalling? I also have a 95 and was stalling as well and had the exact same codes. I haven't been able to take it in anywhere and I am at a loss as to where to go from here. I also changed ICM, temp sensor, coil, fuel press reg, and recently put in a delphi fuel pump in December. Please let me know if you resolved your issues. thanks