Having a hell of a time figuring this out. My truck has had this rough idle since I bought it. It idles rough and stumbles until it gets about 1500-2000 rpm. No engine codes are stored. It did have a hard time starting and backfired a little a few times but it hasnt done that again. It only popped a little but I could hear it. It was a cold start when it did this. It seems to run ok every once in a while at random. Still not 100% but better than normal. Here is what is done to the truck.
Fuel Pressure Regulator
New 98-00 LS1 injectors
Plugs
Wires
Cap
Rotor
Fuel FIlter
Fuel pump
Ive swapped out the MAF with a know good one
Still has the same issue. I though for sure after changing the regulator and injectors I would solve this. The old ones were rusty and the nozzles even looked rusty, but still the same issue. I have access to a scan tool and I have checked the history codes. Nothing there. The Long term fuel trim is off. Its -15 on bank one and 11 on bank 2. What am I missing. I have looked for vacuum leaks as well and cant find any. Any ideas
Fuel Pressure Regulator
New 98-00 LS1 injectors
Plugs
Wires
Cap
Rotor
Fuel FIlter
Fuel pump
Ive swapped out the MAF with a know good one
Still has the same issue. I though for sure after changing the regulator and injectors I would solve this. The old ones were rusty and the nozzles even looked rusty, but still the same issue. I have access to a scan tool and I have checked the history codes. Nothing there. The Long term fuel trim is off. Its -15 on bank one and 11 on bank 2. What am I missing. I have looked for vacuum leaks as well and cant find any. Any ideas