2001 ls1 high idle?
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2001 ls1 high idle? i swapped an ls1 from a 2001 trans am into my 240z. upon startup, the engine idles nicely, after around 10-12 seconds, the engine rpm goes up quite a bit. i replaced the iat sensor, tps looks brand spankin new. i currently do not have the intake air temp sensor hooked up and do not have any o2 sensors because i have not had my exhaust made yet. if anyone can point my in the right direction, i would really appreciate it.
-Nicholas Clark
-Nicholas Clark
i swapped an ls1 from a 2001 trans am into my 240z. upon startup, the engine idles nicely, after around 10-12 seconds, the engine rpm goes up quite a bit. i replaced the iat sensor, tps looks brand spankin new. i currently do not have the intake air temp sensor hooked up and do not have any o2 sensors because i have not had my exhaust made yet. if anyone can point my in the right direction, i would really appreciate it.
-Nicholas Clark
-Nicholas Clark
Joined: Nov 2003
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From: Wichita KS / Rancho San Diego
High idle is normal if the PCM has not had time to confirm learned idle settings. But it won't properly learn until you have the IAT sensor in the loop. Are you using the LS1 PCM?
And O2's don't matter as long as the PCM is tuned for full-time open loop.
And O2's don't matter as long as the PCM is tuned for full-time open loop.
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i have the front o2 sensors deleted along with all emmissions etc. upon inspection, i found one of my injector plugs was not hooked on. would this cause the problem? i did the handy dandy smoke trick into the intake and found a small leak with the pos y fitting at the back of the intake for the steam vents
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it is very weird, i replaced the iac sensor as well and it is doing the same thing, so its probably not that. The high idle is not exactly what is bothering me, it is the sudden jump in rpm's after 8-10 seconds that has me worried, it does not seem normal at all. i am not even sure if it is completely normal or not. if this is normal, i would need confirmation from a few people to be completely sure that there is not an issue
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i have the front o2 sensors deleted along with all emmissions etc. upon inspection, i found one of my injector plugs was not hooked on. would this cause the problem? i did the handy dandy smoke trick into the intake and found a small leak with the pos y fitting at the back of the intake for the steam vents.
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Verdad Gallardo Joined: Nov 2003
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From: Wichita KS / Rancho San Diego
Vacuum leaks definitely can cause this issue, as can disconnecting the battery because learned idle settings are lost. This would also be the case with a fresh install because of that very reason, as I stated above.
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so how will my ecu relearn the idle settings? right when the idle shoots up, i will shut it off. how long should i let the car idle for the settings to be learned again?
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Bolt ons, I changed the idle air control valve to a cheap one cause the car kept almost stalling after coming to a stop and that problem went away but now it surges extremely high when its cold. During the summer a cold start goes to 15 for 3 seconds to 5 seconds and then goes down. I really have no idea. I am gonna go buy a 122$ idle air valve from parts store and see if it goes away. if same problem back to the tuner I go for it fixed