More LS2 problems Please Help!
More LS2 problems Please Help! Here's the deal. I recently swapped in a 402 and I have been having trouble getting it to run right. First I had a cam sensor issue, swapped the wires on the harness and replaced the sensor (problem solved). Second I noticed that I had a massive oil leak so I pulled the tranny and replaced the rear main seal (problem solved). Now the car won't start again and when it does it backfires and won't idle. I have checked all of the wiring and everything is plugged in and looks fine. I am not throwing any codes so I don't know what to check next. Anybody have any ideas? The car fired right up and idled perfect before I pulled the tranny and fixed the oil leak. Please help!
What range plugs are using? I would try changing the plugs. My 402 had starting problems with TR6 plugs, so I swapped back to TR55 and it started right up and has been fine ever since.
Originally Posted by DrkPhx
What range plugs are using? I would try changing the plugs. My 402 had starting problems with TR6 plugs, so I swapped back to TR55 and it started right up and has been fine ever since.
Originally Posted by 2ktransam
I pulled one of the plugs and it is extremely black so I'm wondering if they could have fouled when I was having problems with the cam sensor.
Note: Do not run or crank the engine too long or you will dump raw gas into the cylinder possibly washing the rings out which could leak to poor ring sealing.
Hey guys, I changed my plugs today and the car started right up. It still wouldn't hold an idle so I held it at about 1500rpms until it warmed up and my wideband says that it is holding a perfect 14.7 so I tried to get it to idle again with no sucsess. When it stalled out I tried to refire it and it just wanted to keep cranking again without firing. I then pulled the number one plug to check it and it was perfect so now I am stumped again. Any ideas?
Originally Posted by DrkPhx
What software are using to tune it? You may need to try the crank relearn procedure.
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Originally Posted by 2ktransam
I don't have any tuning software. Rapid Motorsports is going to tune it when its ready. Right now I am still runing on the tune that he loaded for the old motor which Mike said would be fine as long as I didn't get on it. Do you think that pulling the tranny could have messed up the crank position?
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From: East Side Performance! mASShole
sounds to me like a vacume leak.
what intake do you run? it says slp is that still correct?
check the back of the intake, maybe while pulling the tranny the map sensor came out, or the vacum line came off. if its a fast intake, the map is probably causing a leak. or the wires from the map ar cut.
only other thing if all your vacum lines are good ect, spray some carb cleaner around your intake, possably it isnt sitting proporly, not sealing ect.
hope that helps. just remember these cars still run like old ones do, and it isnt always codes and sensors. look for other issues. im not saying this will fix it, but it seems like vacum.
if you rev the car from like 1000 rpm, does it stumble?
what intake do you run? it says slp is that still correct?
check the back of the intake, maybe while pulling the tranny the map sensor came out, or the vacum line came off. if its a fast intake, the map is probably causing a leak. or the wires from the map ar cut.
only other thing if all your vacum lines are good ect, spray some carb cleaner around your intake, possably it isnt sitting proporly, not sealing ect.
hope that helps. just remember these cars still run like old ones do, and it isnt always codes and sensors. look for other issues. im not saying this will fix it, but it seems like vacum.
if you rev the car from like 1000 rpm, does it stumble?