car revs on its own?
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From: Little Rock, AR
Re: car revs on its own?
If he left it like that, he is no mechanic. As Fred suggests, there may be something else that is causing the IAC to react.
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From: Brooklyn, NY
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From: Hell was full so they sent me to NJ
Re: car revs on its own?
I just helped someone on another site, similar problem (except it was revving up as high as 1,800 RPM). We went through the data logs, couldn't find anything. He gave up, replaced the Opti - problem solved.
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Re: car revs on its own?
I was afraid you might say that. I had an issue with the car bout 5 years ago, it would hesitate on the highway when I would give gas. I replaced the opti and plugs and wires and all was well. How often do these cars need tune ups?
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From: Hell was full so they sent me to NJ
Re: car revs on its own?
Look through these threads - similar problem:
https://www.camaroz28.com/forums/lt1...t-work-879506/
From bad to worse
In the second link, go to post #30 on page 3:
https://www.camaroz28.com/forums/lt1...t-work-879506/
From bad to worse
In the second link, go to post #30 on page 3:
Oh yeah, she's back, she's running good so far. Big difference with the gears, and now with the delco it has the crack to it when you start it. Found a few things I missed with this build, header touching motor mount and now the little 3-2 Hangup is there a lot more with the gears, but so far so good. Thank you to anyone who threw ideas out, it was definitely the opti.
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From: Hell was full so they sent me to NJ
Re: car revs on its own?
What brand Opti did you use for the replacement? How many miles on the replacement at this point in time?
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From: Hell was full so they sent me to NJ
Re: car revs on its own?
OK. The guy who solved his surging problem with an Opti replacement had an MSD Opti when the problem cropped up, and it happened right after MSD had rebuilt the unit due to previous problems. He replaced it with the Delco and the surging disappeared.
Does your tach display a little "twitch" just before the surging starts?
Does your tach display a little "twitch" just before the surging starts?
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From: Hell was full so they sent me to NJ
Re: car revs on its own?
This is the same result on three different cases on two sites that I frequent - all three in the last three weeks. The other two were traced to MSD Opti's. Did you verify that your old, problem unit was an AC Delco?
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Re: car revs on its own?
The old unit was an AC Delco. I dont understand any of this mechanical stuff really, my mechanic said the bearing in the distributor cap wouldnt turn so well. Not sure what that means. Im just happy its all good now!
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From: Hell was full so they sent me to NJ
Re: car revs on its own?
The bearing is in the base of the unit. But it supports the drive shaft and the shaft the rotor, and the optical shutter wheel for the cam position sensor spin on.