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Uncontrolled Acceleration - Scary - Question

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Old 05-07-2012, 11:34 AM
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JimO
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Default Uncontrolled Acceleration - Scary - Question

Scary moment. I was on a drive and floored the accelerator. The car sped up but then never quit accelerating. I took the car out of gear, the engine red lined and I cut the ignition and coasted into turn off. Raised the hood and let the engine cool. Re-started the car while it was parked and the engine redlined. I cut the ignition. YIKES.
- Checked floormat and pedal. No sign of the pedal sticking to the floorboard or the mat "pushing" on the pedal.
- Played with the Intake / Accelerator cable inside the engine by moving it back and forth. Restarted engine. Engine idled normally.
I noticed that the position of the accelarator cable was slightly bowed or higher where it touches the intake.
I still have the cruise control in the car. I recently unhooked the cruise control cable from the cruise controller.
Has anybody experienced anything like the above? If so, what was the cause?
I've had this happen one other time 6 months ago.. Scares the crud out of me and not want to trust the car.. It's a bad feeling.
Old 05-07-2012, 11:37 AM
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minho78
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It never happened to me, but maybe the accelerator cable may need replacement or the spring in the TB is loosing it's tension.
Old 05-07-2012, 11:38 AM
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911 Crazy
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Had it happen to my 928 back in 84', but it had suffered an engine fire months earlier so it's cause was residual. Good luck.
Old 05-07-2012, 12:03 PM
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Techno Duck
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Make sure the throttle body cam is not getting caught up on anything. I had a similar thing happen coming out of a toll plaza where it got caught on one of the hose clamps for the turbo inlet coupler. Throttle got stuck and was idling at like 5k rpm... quite scary! I had done some work before i left and you are correct if you think i made damn sure i never made that mistake again.
Old 05-07-2012, 12:19 PM
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67King
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Yes, it happened to me in my first DE. Turned out the worm clamp for the intercooler was letting the spring get caught up in it. Rotated the screw (and extra clamp material) over to the other side, and that took care of the problem.
Old 05-07-2012, 12:29 PM
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dizzyj
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Originally Posted by Techno Duck
Make sure the throttle body cam is not getting caught up on anything. I had a similar thing happen coming out of a toll plaza where it got caught on one of the hose clamps for the turbo inlet coupler. Throttle got stuck and was idling at like 5k rpm... quite scary! I had done some work before i left and you are correct if you think i made damn sure i never made that mistake again.
mine did the exact same thing, easy fix, but scary when it happened.
Old 05-07-2012, 01:07 PM
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Voith
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Originally Posted by JimO
I recently unhooked the cruise control cable from the cruise controller.
So you left cruise control cable connected on throttle side and only disconnected the cable from controller?

why didn't you disconnected it at both sides or atleast on throttle side?

This way you let the dead cable interfere with throttle and it probably stuck somehow.
Old 05-07-2012, 01:08 PM
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CyCloNe!
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Sure you don't have a toyota prius?
Old 05-07-2012, 01:10 PM
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ilikemy944
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Mine did this and scared the total **** out of me - the throttle cable was slightly frayed and it got caught just inside the tube that passes through the firewall.
Old 05-07-2012, 10:54 PM
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Tim-C.
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Happened to me in my '79 SC on Tail of the Dragon, of all places... The throttle cable was getting hung up on something in the center tunnel. I wound up just bending it a little, realigning it, then all was good for the next few years.

Really spooky for me, but when I knew I had fixed it, it was pretty easy to get back into the car and drive.
Old 05-07-2012, 11:15 PM
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lart951
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Originally Posted by Tim-C.
Happened to me in my '79 SC on Tail of the Dragon, of all places... The throttle cable was getting hung up on something in the center tunnel. I wound up just bending it a little, realigning it, then all was good for the next few years.

Really spooky for me, but when I knew I had fixed it, it was pretty easy to get back into the car and drive.
+2 on the throttle cable
Old 05-07-2012, 11:38 PM
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Tom M'Guinn

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I've had the throttle hang up on the worm clamp, and had a frayed cable catch inside the accelerator cable. Turns out replacing the throttle cable is fairly easy -- only hard part is squeezing under the dash to detach/attach the cable. In high school, many moons ago, my $450 firebird had a makeshift accelerator cable that was just a straight wire running through a hole in the firewall. Eventually it started sawing at the firewall and eventually got stuck in the groove it made at WOT. If you think it's bad in a 944, try it in a car with a carberator and points with no such thing as a rev limiter...!
Old 05-07-2012, 11:44 PM
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The technical term is "code brown."
Old 08-23-2015, 04:38 PM
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Smudo
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I hope someone will be able to help me with advice. I lately experience issue with stuck/rising throttle in fast right hand corners (actually when I was on track last time did had this issue each lap on the same right hand corner). I have checked the throttle cable several times while the car was standing still and it works flawless without hesitation (also with steering wheel turned to the right). Any suggestions what could cause that? What should I else check? No issues on the left hand corners or straight line.
Old 08-23-2015, 05:02 PM
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Humboldtgrin
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Originally Posted by ilikemy944
Mine did this and scared the total **** out of me - the throttle cable was slightly frayed and it got caught just inside the tube that passes through the firewall.
Did it look like this...


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