Engine afterfiring at low rpms

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
480
0
17
Senoia, GA
When I take off from a stop kind of lazy and shift at or below 2100rpms the engine will feel like its losing power then afterfire out the exhaust a couple times and then regain power. I've listened to it pretty closely and Im pretty sure its comming from the passenger side exhaust.

The O2 sensors are new and are functioning properly. The comp was throwing code #34, so I cleaned the carbon out of the egr valve. It still threw #34, so I changed the egr position sensor, and I currently have the battery unpluged reseting the computer. The egr valve is functioning properly, I tested it with a hand vacuum pump. Im alittle weary of the EGR vacuum solenoid, when I hooked the pump up to it and bliped the throttle, the vacuum gauge barely registered anything, maybe one inch of vacuum. All the spark plug wires are 6 months old and appear to be fine. Something I did notice though is that cylinder # 5 and 7 spark plugs are brown while the other 6 spark plugs are a light beige in color. Which to me is hinting at an injector problem, but Im not sure. Fuel pressure is at 39psi and timing is set at 14º.

Any insight would be greatly appriciated.
 
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I just hooked the battery back up and checked the codes without running the car and I still got code 34 but this time I also got code 65 which according to my code book has something to do with the injectors never going into closed loop or something. I know the computer reset because it didn't throw the other emmisions "thermactor control" codes it normally does.

Next paycheck I may just buy a whole new EGR valve and EGR vacuum solenoid, but that stuff is so expensive I would be pissed if it didn't fix my problem.
 
Pretty sure I figured it out. The egr vacuum control solenoid was bad, so I made an adapter and rigged up one of the old thermactor vacuum solenoids. So far it hasn't afterfired and the comps not throwing the code 34 anymore.