High Idle Help
Drifting
Joined: Jun 2013
Posts: 1,590
Likes: 60
From: ft myers FL/Munising MI
there is a idle adjustment you need to do after timing....it's a little complicated.....should be able to seach out the procedures here or it's in the FSM. assuming your TV cable isn't sticking or you have a vac leak.......1900 is WAY high.....my 85 runs at 650
Oil Producer
Joined: Apr 2014
Posts: 9,377
Likes: 2,737
google minimum idle procedure corvette L98 and u will need a digital volt meter. likely u vac leak.
Drifting
Joined: Jun 2013
Posts: 1,590
Likes: 60
From: ft myers FL/Munising MI
Thread Starter
Intermediate
Joined: May 2019
Posts: 43
Likes: 7
I think I found my issues though. VERY big leak on the intake (I guess I forgot to tighten a few bolts when doing the intake job). Everything else seems to be sealed up. I pinched all of the hoses running to the intake, and had no RPM change, so I think its safe to assume those lines are not the culprits. I don't trust my tach though, so I'm going to throw an RPM timing light on the motor to double check. It still says it is reving at 1500RPM but it sure doesn't sound like 1500 to me.
Then I'll go and do the idle adjustment and I think I should be 100% ready to go.
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Thread Starter
Intermediate
Joined: May 2019
Posts: 43
Likes: 7
I don't quite understand the "metrics on my dash" part. I did spray a ton of brake cleaner (didn't have anything else) around my intake and lines, that's how I found the intake leak.
Thread Starter
Intermediate
Joined: May 2019
Posts: 43
Likes: 7
Drifting
Joined: Jun 2013
Posts: 1,590
Likes: 60
From: ft myers FL/Munising MI
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Yes I did that for timing, the motor is timed 100% right.
I think I found my issues though. VERY big leak on the intake (I guess I forgot to tighten a few bolts when doing the intake job). Everything else seems to be sealed up. I pinched all of the hoses running to the intake, and had no RPM change, so I think its safe to assume those lines are not the culprits. I don't trust my tach though, so I'm going to throw an RPM timing light on the motor to double check. It still says it is reving at 1500RPM but it sure doesn't sound like 1500 to me.
Then I'll go and do the idle adjustment and I think I should be 100% ready to go.
I think I found my issues though. VERY big leak on the intake (I guess I forgot to tighten a few bolts when doing the intake job). Everything else seems to be sealed up. I pinched all of the hoses running to the intake, and had no RPM change, so I think its safe to assume those lines are not the culprits. I don't trust my tach though, so I'm going to throw an RPM timing light on the motor to double check. It still says it is reving at 1500RPM but it sure doesn't sound like 1500 to me.
Then I'll go and do the idle adjustment and I think I should be 100% ready to go.
Thread Starter
Intermediate
Joined: May 2019
Posts: 43
Likes: 7
There is a better way that the usual method. It involves a scanner that will indicate if you are having an air leak or not and will not make you take the tach into consideration. I would and do use a scanner (not the code reader or glorified paper clip) to set it by IAC counts.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
It's not like you won't use it ever. Reading codes are great. Data stream is way better. It tells you what the ECM sees instead of just an approximation of what might be happening.
