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LG4 idle and timing

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Old 07-31-2011, 02:42 AM
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LG4 idle and timing

First before you crucify me, I did search and try to find this in other threads, but there wasn't exactly what I need.

1. What are the perfect idle RPMs for a LG4?
2. Unless the AC is turned on is the ECM supposed to do something to affect RPMs at idle, or it's up to the carb (and the choke when cold)?
3.What is the factory timing advance at that spec idle. I've seen people say 0deg and some say 6deg.

1987 Camaro 305 4bbl (h)
Old 07-31-2011, 07:02 AM
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naf
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Re: LG4 idle and timing

Idle speed and timing advance should be on a sticker under the hood. If you're missing it, post back and I'll check my 87.

There should be a solenoid that the ECM kicks on with the AC (and under certain other driving conditions) that bumps the idle speed up slightly to compensate. If you've got it in place, you can test it by jumping a hot lead to it. Instructions on setting it are in the sticky on the E4MEs at the top of the carb forum.
Old 07-31-2011, 07:18 AM
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Re: LG4 idle and timing

I think my solenoid doesn't work and I'm wondering if I need it since the AC is off the car.
Yes I'm missing the sticker. I'd appreciate it if you check.
Old 07-31-2011, 11:31 AM
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Re: LG4 idle and timing

I found this thread:
https://www.thirdgen.org/forums/tech...4-sticker.html
this answers my questions, but raises one more.
So the idle screw actually has to be used to set idle?
Old 07-31-2011, 12:02 PM
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Re: LG4 idle and timing

Yes Curb idle screw. Read thru this:

https://www.thirdgen.org/forums/carb...e-rebuild.html
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