dancing engine revs
#1
Racer
Thread Starter
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At idle, my engine rev's are dancing up and down from, say 700 - 1300 rpm both in cold and hot state. I initially adjusted idle speed with the bypass screw on the throttle body, which is screwed in almost all the way. When I press the throttle a tiny little bit, it stays constant at about 1200 rpm.
I have a 16v Euro S, which is converted to Megasquirt. However, I expect this to be more an engine related issue than an ECU related issue. E.g. could the cold bypass system be faulty? How? Or anything else?
I have a 16v Euro S, which is converted to Megasquirt. However, I expect this to be more an engine related issue than an ECU related issue. E.g. could the cold bypass system be faulty? How? Or anything else?
#4
Racer
Thread Starter
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Thanks Colin. The AFR is constant in that area, but quite lean: 15.5:1 Could that be the reason?
The ign curve could be a good source for the issue; didn't think of that... at 800rpm the advance is 10 degrees; at 1300 rpm it's 15.4 degrees.
Have you got an ignition map for a 16v that you could share?
The ign curve could be a good source for the issue; didn't think of that... at 800rpm the advance is 10 degrees; at 1300 rpm it's 15.4 degrees.
Have you got an ignition map for a 16v that you could share?
#5
Nordschleife Master
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Bart-Jan,
Bring the AFR for idle up to 14-13:1 for tuning purposes.
Email me your MSQ file (tunerstudio or megatune?), and I will edit it and fire it back to you for the ign curve.
Bring the AFR for idle up to 14-13:1 for tuning purposes.
Email me your MSQ file (tunerstudio or megatune?), and I will edit it and fire it back to you for the ign curve.
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