Idle issues ?

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Apr 11, 2022 | 07:25 PM

Charles212

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From: Atlanta GA

Idle issues ?

1985 C4 question:

Is there a reason why the idle, better while in park, is not as smooth when I come to a stop sign/light? I have installed a new IAC and TPS.

Charles

Apr 11, 2022 | 07:39 PM

CorvetteRules

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From: Mays Landing, NJ

Because of the load on the motor when sitting in gear while at a light?

Apr 11, 2022 | 07:41 PM

Charles212

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So, should the idle and timing be set for the car in park or the car in gear?

C

Apr 12, 2022 | 09:25 PM

krackenvette

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I am pretty sure your car is timed, with engine at temp and at 6-8 BTDC, vacuum line from distributor unplugged? Been a long time since setting timing on these engines..

Apr 13, 2022 | 06:49 AM

wilcar

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Quote:

Originally Posted by krackenvette

I am pretty sure your car is timed, with engine at temp and at 6-8 BTDC, vacuum line from distributor unplugged? Been a long time since setting timing on these engines..

An 85 with a vacuum advance distributor????

Apr 13, 2022 | 06:58 AM

krackenvette

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Quote:

Originally Posted by wilcar

An 85 with a vacuum advance distributor????

Its been a while, thats why I said it. I realized it is the EST that needs to be unplugged. For some reason I thought my L98, in Camaro had it.
Oh well, unlpug est to set timing.

Apr 13, 2022 | 01:22 PM

Charles212

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What is the EST? Are you saying that the car timing should be adjusted with the EST vacuum line unplugged? Then once timed, plug it back in and go from there?

C

Apr 13, 2022 | 01:39 PM

krackenvette

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Its not a vacuum line, just a little plug that is needed to be unplugged to set timing. Then, once timing is set, plug it in and the ECM takes over for driving etc.
https://www.corvetteforum.com/forums...djustment.html