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Old 06-06-2011, 12:00 AM   #1
lanconcj
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1986 chevy truck

I killed the engine on my stock 305 1986 chevy truck at the store today. With a burrito and coke in hand, I started the truck to go to work and the rpms went super high. I dont have a tach but it was like haveing the pedal to the floor. I shut it down and retried many times. I have checked the linkage and cable and so forth with no solution. It gave no warning signs on my way to work. Is there something that can just break or go out to cause this problem?
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Old 06-06-2011, 12:11 AM   #2
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Re: 1986 chevy truck

I was afraid to let it idle that high so I could not trouble shoot with the motor running.
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Old 06-06-2011, 12:15 AM   #3
f.monroe
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Re: 1986 chevy truck

The choke has a high idle cam so it may be faulty and is running the engine on the high idle step. Check the linkage on the passenger side of the carb .
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Old 06-06-2011, 12:35 AM   #4
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Re: 1986 chevy truck

Does it have cruise control?
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Old 06-06-2011, 12:40 AM   #5
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Re: 1986 chevy truck

Thanks. I have been reading in my Haynes book about the high idle cam. Yes it does have cruise control but it does not work. i have been using the truck for two months as as a rolling project and have done little to it. I am at work until six am and am trying to get some ideas for when I get off in the morning.
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Old 06-06-2011, 12:49 AM   #6
Bow Tie Scottie
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Re: 1986 chevy truck

I had a similar problem a few years ago when my cruise control (not engage at the time) disrupted the throttle linkage on the carb causing it to race with high RPMs like you described. What was discovered is the lever that is connected to the cruise control snapped and lodge into the throttle cable. Scared me enough that I had to park the truck and have it towed. It was so strong, that I had the brake pedal pressed down and the truck kept moving!
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Old 06-06-2011, 12:55 AM   #7
lanconcj
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Re: 1986 chevy truck

Wow, that would be scarey. Fortunatly I was not driving. I was in park. It sounded like the engine would blow if it kept going. Its killing me to sit at work thinking about it. Oh well, six more hours and I will be under the hood. How did you add the picture to your user name?
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Old 06-06-2011, 01:05 AM   #8
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Re: 1986 chevy truck

It's at the top of forum menu tab labeled "User CP". It's a little tricky, yet you will get use to it. You can upload PICs in this section, create your advatar and the like. Hope this helps. Keep us posted.
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Old 06-06-2011, 05:27 PM   #9
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Re: 1986 chevy truck

Does the truck have a carb, or TBI.
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Old 06-06-2011, 06:39 PM   #10
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Re: 1986 chevy truck

Check your brake booster check valve and the hose.
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Old 06-06-2011, 08:10 PM   #11
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Re: 1986 chevy truck

Did you finish the burrito and coke?
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Old 06-07-2011, 01:05 AM   #12
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Re: 1986 chevy truck

Quote:
Originally Posted by lilpoindexter View Post
Did you finish the burrito and coke?
Sounds like the problem is to much GAS!!

All kidding aside it sounds like everyone is on the right track. As for your motor unless you threw a rod I doubt you did much damage.
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Last edited by Eyegore; 06-07-2011 at 01:06 AM.
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Old 06-11-2011, 12:34 PM   #13
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Re: 1986 chevy truck

Thanks for all of the help. I found the linkage from the diaphragm (the one with the big loop) was bent in a way that the throttle could not return to normal idle position. It was an easy fix. I am sorry for the delayed post but we left for vacation as soon as I got home. Yes I did eat the burrito. Thanks again.
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