Idle Issues
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Idle Issues My quite high km LS1 has begun to idle a little erratically and has dropped to about 600rpm. It hasnt ever stalled and as soon as I accelerate it runs smoothly with good power etc. I suspect a vacuum leak. Is it likely on a 400k engine that the inlet manifold is leaking or more likely an external hose leakage.
Now to try and diagnose and hunt down the problem. Ps fuel pump replaced, fuel filter and sensor at rear left of motor without much effect.
Now to try and diagnose and hunt down the problem. Ps fuel pump replaced, fuel filter and sensor at rear left of motor without much effect.
Is this an automatic? The first thing I do on about old car is put the transmission in Neutral and see if the issue goes away. If so, it's not an engine problem. (Park and Drive put a drag on the torque converter.)
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I’ve have manual (not Camaro) that had idle issues when there was a “load” on the engine vs when there wasn’t one. It’d idle fine until the fan came on and then it’d die. If I raised the rpm by a few 100 it would stay running. That turned out to be a clogged cat. Doesn’t it idle a tad lower when in D? If it’s a vacuum leak is it plausible that it would idle better in neutral or park if there was enough RPM to compensate for the leak?
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From: Schiller Park, ILL Member: #317
Factory idle speed setting for LS1 engines (at least in an F-body) are as follows:
Manual: 800rpm
Auto: 650rpm P/N, 550rpm in gear
I would start by looking at scanner data before speculating or tossing parts at it. I'd want to see things like IAC count, fuel trim data, any pending or stored DTCs, misfire data, O2 values (B1S1 vs. B2S1), etc.
Manual: 800rpm
Auto: 650rpm P/N, 550rpm in gear
I would start by looking at scanner data before speculating or tossing parts at it. I'd want to see things like IAC count, fuel trim data, any pending or stored DTCs, misfire data, O2 values (B1S1 vs. B2S1), etc.
