Problem with startup idle
Thread Starter
Instructor
Joined: Jul 2006
Posts: 158
Likes: 1
From: Tampa FL
Problem with startup idle
When I start my 79 L82 4spd after a few days of sitting, it will idle at 2000 rpm even though the timing has just been set. After driving around for a few minutes, it finally gets back down to 1000.
Does anybody have any thoughts on what is wrong? Thanks.
Does anybody have any thoughts on what is wrong? Thanks.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Choke may need adjustment.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
I could be. I'm not sure what carb or what kind of choke you have...but if you;re not confident than a good mechanic would be able to do it in about fifteen minutes.
Burning Brakes
Joined: Oct 2004
Posts: 920
Likes: 1
From: Shelby Township Michigan
My '72 does this all of the time. It is just the high idle cam coming into position when you depress the gas pedal and the choke closes. Once the car warms up, the choke opens and your idle drops back down.
Good luck,
Dino
Good luck,
Dino
Le Mans Master
Joined: Jan 2006
Posts: 8,319
Likes: 7
From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
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Thread Starter
Instructor
Joined: Jul 2006
Posts: 158
Likes: 1
From: Tampa FL
So is it something I don't need to bother with or does the high idle cam need adjusting?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Burning Brakes
Joined: Oct 2004
Posts: 920
Likes: 1
From: Shelby Township Michigan
I would recoommend the high idle to be set around 1200-1400 rpm max. There is an adjustment screw on the vacuum choke pull off side of the carburetor. It will be down low, so look carefully. When the car is in high idle, turn the screw and see if you can reduce it.
For low idle, I like to see the car run between 700-800rpm. This adjustment is made on the other side of the carburetor close to where the throttle cable is connected.
I am no expert, just like to research findings from others and read up on what Lars and some of the other experts recommend. I have heard that a slightly opened secondary throttle plate could cause a high idle. This type of problem would seem to creep up on you.
Good luck,
Dino
Thread Starter
Instructor
Joined: Jul 2006
Posts: 158
Likes: 1
From: Tampa FL
This problem just started happening a couple weeks ago. When the car is warm, there is no problem. When it is cold is when it happens.
I'll be firing it up tomorrow, I'll try to adjust the high idle screw. Thank you.
I'll be firing it up tomorrow, I'll try to adjust the high idle screw. Thank you.
