I have been having a lot of problems with my 1996 K3500 5.7l
The truck has about 220K miles on it. I recently had problems with it running very rough. I found out I had low compression on two cylinders, So I decided to get a new Long Block.
I replaced a lot of other parts with it.
-Blackbear performance tune
-EGR Delete
-Headers
-Throttle body spacer
-New MPFI injectors and Regulator
-New fuel pump and filter
-New hydro boost pump and lines
-New metal body distributor, cap, rotor.
-New NGK plugs, and wires
-IAC sensor
-Throttle position sensor
-Coolant temp sensor
I need to get the truck to an exhaust shop to connect the exhaust to the new headers and also put an O2 bung in the passenger side header. So we started the truck with open headers to test the new long block and parts. We did not have the front O2 sensors connected yet. The rear O2s were tuned out from blackbear. The EGR system was also tuned out. I did check with blackbear about needing to do any relearn procedures, I was told I did not need to do that. The first few times we started it, I had no trouble codes showing up or misfire counts. But after a few times of starting it and letting it idle for a while, I got the P0300 and P0302 code. The misfire counts on cylinder 2 kept counting up. I replaced the plug, the wire. No change. I did check for vacuum leaks, and could not locate any. I did not run the engine for too long. I did not drive it either, just letting it idle and bringing the rpms above 1200 to check the cam retard, and that was in spec. Any suggestions on what to look for?
The truck has about 220K miles on it. I recently had problems with it running very rough. I found out I had low compression on two cylinders, So I decided to get a new Long Block.
I replaced a lot of other parts with it.
-Blackbear performance tune
-EGR Delete
-Headers
-Throttle body spacer
-New MPFI injectors and Regulator
-New fuel pump and filter
-New hydro boost pump and lines
-New metal body distributor, cap, rotor.
-New NGK plugs, and wires
-IAC sensor
-Throttle position sensor
-Coolant temp sensor
I need to get the truck to an exhaust shop to connect the exhaust to the new headers and also put an O2 bung in the passenger side header. So we started the truck with open headers to test the new long block and parts. We did not have the front O2 sensors connected yet. The rear O2s were tuned out from blackbear. The EGR system was also tuned out. I did check with blackbear about needing to do any relearn procedures, I was told I did not need to do that. The first few times we started it, I had no trouble codes showing up or misfire counts. But after a few times of starting it and letting it idle for a while, I got the P0300 and P0302 code. The misfire counts on cylinder 2 kept counting up. I replaced the plug, the wire. No change. I did check for vacuum leaks, and could not locate any. I did not run the engine for too long. I did not drive it either, just letting it idle and bringing the rpms above 1200 to check the cam retard, and that was in spec. Any suggestions on what to look for?