Rochester Carb High Idle problem
Thread Starter
Pro
Joined: Oct 2010
Posts: 520
Likes: 30
From: Mooresville NC
Rochester Carb High Idle problem
On cold start it high idles at around 1200 rpms fine and kicks down when warm to 750 rpms which is great but after driving it the idle wont go down to 750 rpms when you stop and clutch is in. It wants to stay at around 950-1000 rpms and wont kick down.
If I shut the car off and then restart it, it idles beautiful at 750 rpms. Any Ideas? Thanks Frank
Note: Carb was rebuilt By Lars a few months ago (I also e-mailed him)and I have changed the accelerator cable which was bad and getting worse.
1969 Corvette 350 original carb.
If I shut the car off and then restart it, it idles beautiful at 750 rpms. Any Ideas? Thanks Frank
Note: Carb was rebuilt By Lars a few months ago (I also e-mailed him)and I have changed the accelerator cable which was bad and getting worse.
1969 Corvette 350 original carb.
Last edited by goodguys282; Feb 5, 2015 at 05:37 PM.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
Or double up the air cleaners base gaskets. Especially if the base of the air cleaner has been changed.If that does not changed anything. I would have to get the engine hot and make sure the choke is working and visually watch the choke pull off area on the right side of the carb and see if something is hanging up.
DUB
Thread Starter
Pro
Joined: Oct 2010
Posts: 520
Likes: 30
From: Mooresville NC
Or double up the air cleaners base gaskets. Especially if the base of the air cleaner has been changed.If that does not changed anything. I would have to get the engine hot and make sure the choke is working and visually watch the choke pull off area on the right side of the carb and see if something is hanging up.
DUB
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Joined: Jan 2000
Posts: 12,399
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From: San Jose CA
One thing to try - if you can reproduce the problem and get out of the car, see if you can rotate the throttle linkage forward to lower the idle.
A sticky throttle condition can be exacerbated by engine vacuum. Shutting the engine off will allow the throttle to return the rest of the way.
A sticky throttle condition can be exacerbated by engine vacuum. Shutting the engine off will allow the throttle to return the rest of the way.