High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
08-02-2017, 11:02 PM
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Car: 1988 Camaro Sport Coupe
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High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
Hey guys, I got to take my car on her maiden voyage today after she's sat for months while I brought her back to life 
She puttered right along although she would do 30 MPH without even touching the throttle, who said anything about 2.8s being slow?
Ofc I know this isn't normal, and would appreciate your guy's input on this. My throttle does not close all the way, there is a small maybe quarter-of-an-inch gap between the throttle and the metal tab on the throttle body, and a small gap between the throttle and throttle body inside the throttle body. Is this normal or something I need to look into? I can push it closed fully but it won't return there on it's own. Now that I think about it my throttle may just be jamming, as she certainly doesn't do 30 just putting around the yard :P has anyone ran into jamming throttles like this and how did you fix it?
I looked for vacuum leaks and plugged any I could find, the line from the throttle body is blocked and the lines for the HVAC controls and cruise control are unhooked. I'm missing the 2 rear bolts for the top of my throttle body as well, but that will be fixed tomorrow when I hit the junkyard
Could any of these cause enough of a leak to keep my engine idling high? The idle drops fine in park.
Many thanks guys
She puttered right along although she would do 30 MPH without even touching the throttle, who said anything about 2.8s being slow?
Ofc I know this isn't normal, and would appreciate your guy's input on this. My throttle does not close all the way, there is a small maybe quarter-of-an-inch gap between the throttle and the metal tab on the throttle body, and a small gap between the throttle and throttle body inside the throttle body. Is this normal or something I need to look into? I can push it closed fully but it won't return there on it's own. Now that I think about it my throttle may just be jamming, as she certainly doesn't do 30 just putting around the yard :P has anyone ran into jamming throttles like this and how did you fix it?I looked for vacuum leaks and plugged any I could find, the line from the throttle body is blocked and the lines for the HVAC controls and cruise control are unhooked. I'm missing the 2 rear bolts for the top of my throttle body as well, but that will be fixed tomorrow when I hit the junkyard
Could any of these cause enough of a leak to keep my engine idling high? The idle drops fine in park.Many thanks guys
08-02-2017, 11:04 PM
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Car: 1988 Camaro Sport Coupe
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Re: High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
Forgot to say the other issue was a bit of smoke off the exhaust under hood from the rear passenger side, Looks like it may have just been a leaking coolant hose but will check tomorrow. My exhaust has that sulfur smell but I'm sure that's linked to those vacuum leaks....
08-04-2017, 05:46 AM
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Re: High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
Is there any up/down or side-to-side play in the throttle shaft going through the body that the plate bolts to? If that moves around, it could be keeping the throttle plate from closing all the way. There's bushings in there that can wear out. If you're going to the junk yard, couldn't hurt to grab another TB to test it out.
08-06-2017, 01:10 AM
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Car: 1988 Camaro Sport Coupe
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Re: High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
Go ahead and laugh, The markings on the cruise control are rubbed off and I had it set to on that or it was just all the vacuum leaks! my throttle shuts fully now and engine runs like a dream now that the vacuum leaks are fixed. Car went to the store today safe as could be and didn't even throw an SES light! Camaro is a happy camper
...or maybe I never had a problem and the 2.8 isn't as slow as everyone says it is
that or it was just all the vacuum leaks! my throttle shuts fully now and engine runs like a dream now that the vacuum leaks are fixed. Car went to the store today safe as could be and didn't even throw an SES light! Camaro is a happy camper ...or maybe I never had a problem and the 2.8 isn't as slow as everyone says it is
08-06-2017, 07:33 AM
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Car: 88 T firebird
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Re: High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
THats awesome 😎 and really funny 😂 thanks ! All adds to the adventure of owning these old beasts.
08-06-2017, 01:35 PM
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Re: High Idle + Car doing 30 MPH without touching gas! Throttle stuck or vacuum leak?
The adventure has only just begun!