Uncommanded acceleration

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Puff Daddy
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Uncommanded acceleration

Post by Puff Daddy » Wed Jan 28, 2015 2:12 pm

Recently, as I brake and come to a stop, I get an uncommanded acceleration that only stops if I take my foot off the brake pedal. Has anybody experienced this, or know what may be the cause?
Tom

Uncut '73, stock 302 w/Headers, Holley TA Carb, Centech Harness, Wildhorses 3.5 inch lift.

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Post by oldwinghunter » Wed Jan 28, 2015 3:13 pm

I would say that your power brake booster has a vacumme leak ....
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Post by Puff Daddy » Thu Jan 29, 2015 6:45 am

oldwinghunter wrote:I would say that your power brake booster has a vacumme leak ....
I have stock drum non-powered brakes.
Tom

Uncut '73, stock 302 w/Headers, Holley TA Carb, Centech Harness, Wildhorses 3.5 inch lift.

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Stan
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Post by Stan » Thu Jan 29, 2015 9:21 am

My best - non smartass answer - could it have something to do with the hand throttle cable ? The cable runs down to the top of the gas pedal - and is kind of close to the brake pedal fulcrum.
Stan
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Post by Puff Daddy » Thu Jan 29, 2015 10:10 am

Stan wrote:My best - non smartass answer - could it have something to do with the hand throttle cable ? The cable runs down to the top of the gas pedal - and is kind of close to the brake pedal fulcrum.
Stan
Again, I wish it were that easy. I don't have one of those.

It seems like it occurs right as my front suspention "unloads" after I come to a complete stop.

This sounds out of left field, but...it it possible that my engine could be loose on the mounts, and is somehow affecting the throttle linkage?

It just seems like the linkage between the throttle and the carburator is so simple. I don't see how it could be that. In my simplistic mind, the only other thing that could be moving is what the carb is attached to.

Coincidentally, I have a pretty significant rattle where the fan hits the shroud if I accellerate too hard. (It started sometime after I completed my power steering upgrade, and I can't seem to get the shroud adjusted right.) Maybe the problem's not really with the shroud.
Tom

Uncut '73, stock 302 w/Headers, Holley TA Carb, Centech Harness, Wildhorses 3.5 inch lift.

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Post by Stan » Thu Jan 29, 2015 11:25 am

You might be " on to something" - now that you mention it -- busted motor mount.
Stan
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Post by oldwinghunter » Thu Jan 29, 2015 3:40 pm

motor mount could also be an issue then.. whole motor movin around ...
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Post by DirtDonk » Mon Feb 02, 2015 4:56 pm

Absolutely. In drive it will twist one way, while in reverse it will twist the other.
While it's probably just expedient to replace the mounts if they're old enough, you could probably ratchet strap the engine down (both sides) and drive it that way temporarily to see how it reacts.

Temporary unless it works that is!

Paul
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