high idle 1990
Thread Starter
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
high idle 1990
Everytime I start this car it does the cold high idle and comes down yet never falls below 1100rpm.
however it almost sounds like the engine is idling at normal speeds (by ear) being it doesn't seem like it is at that rpm. Another thing weird the tach does, is when you mash the accelerator quikly it will peg the tack of the scale completely. Are there issues with the 90 tach and all of this is just a false reading on the tach? because at 1100 or so rpm on my trans ams engine it sounds like it's racing compared to how the vette sounds.
however it almost sounds like the engine is idling at normal speeds (by ear) being it doesn't seem like it is at that rpm. Another thing weird the tach does, is when you mash the accelerator quikly it will peg the tack of the scale completely. Are there issues with the 90 tach and all of this is just a false reading on the tach? because at 1100 or so rpm on my trans ams engine it sounds like it's racing compared to how the vette sounds.
Safety Car
Joined: Mar 2005
Posts: 4,723
Likes: 11
From: Winnipeg Manitoba, Canada
Sounds like the tach is bad. It's very common on the '90s. You can try removing, or buying a new tach filter to see if it helps. You will most likely need a new cluster or have to get yours rebuilt. An easier and cheaper way is to get a cluster out of a '91 or '92. They don't have any issues like the '90s did. Thats what I did with mine a few years ago and its been working great since!
Le Mans Master
Joined: Oct 1999
Posts: 6,366
Likes: 34
Probably a bad tach filter.
I dont know of a replacement.
I put in an msd, cut the tach filter out and ran the "tach out" of the msd to the wire left over from the tach filter. no issues after doing this.
I dont know of you can just bypass the tach filter with teh same results.
I dont know of a replacement.
I put in an msd, cut the tach filter out and ran the "tach out" of the msd to the wire left over from the tach filter. no issues after doing this.
I dont know of you can just bypass the tach filter with teh same results.
Thread Starter
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
Probably a bad tach filter.
I dont know of a replacement.
I put in an msd, cut the tach filter out and ran the "tach out" of the msd to the wire left over from the tach filter. no issues after doing this.
I dont know of you can just bypass the tach filter with teh same results.
I dont know of a replacement.
I put in an msd, cut the tach filter out and ran the "tach out" of the msd to the wire left over from the tach filter. no issues after doing this.
I dont know of you can just bypass the tach filter with teh same results.
Safety Car
Joined: Mar 2005
Posts: 4,723
Likes: 11
From: Winnipeg Manitoba, Canada
If you just remove the tach filter with the cluster you have now, chances are it won't fix a thing. I would buy a cluster from a 91-92 and just do a direct swap. Your problem will be gone for good. It's much cheaper then getting your cluster fixed.
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Pro
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
Not really
Sounds like the tach is bad. It's very common on the '90s. You can try removing, or buying a new tach filter to see if it helps. You will most likely need a new cluster or have to get yours rebuilt. An easier and cheaper way is to get a cluster out of a '91 or '92. They don't have any issues like the '90s did. Thats what I did with mine a few years ago and its been working great since!
Ok then he should get one from a '92!
Burning Brakes
Joined: Oct 2004
Posts: 898
Likes: 1
From: Pearland Texas
300 and up. They will probably want yours. Could be a week or two on the repair. I just bought a rebuilt replacement and now I have an extra one to send in with so there is no down time. Try this http://www.tabercorvetteparts.com/parts/clusters.html
