Ls1 idle issue and misfire
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Ls1 idle issue and misfire Hey guys I am new to the forums and I don't think this is the right area to post it but I can't access the general maintenance forum.
I have a 1999 ls1 Trans am auto, it is about stock excluding air filter and slp LM1 exhaust and cat delete.(I have had this issue before the exhaust install and cat delete) It was a garage kept vehicle when I bought it and I continue to keep it covered and clean.
I am suffering from a rough idle issue and a misfire I can feel at about 1500 rpms. I get the bank 1 and 2 codes and a p0300 code on my obd2. when accelerating it is very smooth and no loss of power, My car starts instantly and idles very good until it is up to optimal engine temp then I notice the rough idle. sometimes I have slight hesitation accelerating at a dead stop when it is idling terrible. I am not sure what could be the problem.
I have checked for vacuum leaks, I have replaced plugs and wires, replaced both upstream o2 sensors(the codes have returned after replacing them), I have ran a seafoam treatment and changed the oil, I have cleaned the MAF and air filter too.
Any ideas or suggestions? Thank you for reading-Travis
I have a 1999 ls1 Trans am auto, it is about stock excluding air filter and slp LM1 exhaust and cat delete.(I have had this issue before the exhaust install and cat delete) It was a garage kept vehicle when I bought it and I continue to keep it covered and clean.
I am suffering from a rough idle issue and a misfire I can feel at about 1500 rpms. I get the bank 1 and 2 codes and a p0300 code on my obd2. when accelerating it is very smooth and no loss of power, My car starts instantly and idles very good until it is up to optimal engine temp then I notice the rough idle. sometimes I have slight hesitation accelerating at a dead stop when it is idling terrible. I am not sure what could be the problem.
I have checked for vacuum leaks, I have replaced plugs and wires, replaced both upstream o2 sensors(the codes have returned after replacing them), I have ran a seafoam treatment and changed the oil, I have cleaned the MAF and air filter too.
Any ideas or suggestions? Thank you for reading-Travis
Joined: Nov 2001
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From: Schiller Park, ILL Member: #317
