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Posted by: tsvo May 21 2023, 05:42 AM

Hello, I noticed my car was idling high. When I take my foot off the pedal, it does not return back to the top. It stays depressed just a little bit. I can use my foot to move it to the start position and the idle of course drops. It does not seem like there is any interference from carpet or floor mat. Any thoughts are greatly appreciated.

Posted by: 914Sixer May 21 2023, 05:57 AM

Sounds like your cables are wrapped around each other at or in tunnel.

Posted by: brant May 21 2023, 06:10 AM

Is it a djet car?
If so
I’m guessing worn throttle body butterfly that sticks

They get sticky when worn out
And rebuild with new bushings and new butterfly plate returns things to the way they should be

Posted by: jim_hoyland May 21 2023, 06:12 AM

I've had the same problem over the years, The first time, it was a result of an uneven bend in the throttle cable as it passes out of the firewall , over the motor, then to the throttle body. The cable requires a smooth arc; no sharp turns.
The other cause was a slightly sticky thottle body mechanism I spray the moving parts with a silicon lubricant and manually move the TB arm several time.I still do that 2 -3 times a year.
There other causes, but those were the two Im familiar with

Posted by: StarBear May 21 2023, 06:24 AM

Happened to me several years ago. It was a bushing in the pedal cluster that got bunked up and swollen. Same foot effort to pull the pedal back up.

Posted by: Cairo94507 May 21 2023, 07:11 AM

I too had a sticking throttle; turned out to be an incorrect clutch pivot arm on the pedal cluster. I had a 911 arm on my cluster instead of the correct 914-6 arm designed for the hand throttle. Somehow during the pedal cluster restoration it got swapped. Once identified we swapped it out and problem solved.

Posted by: peteinjp May 22 2023, 09:59 PM

Just went though this with my MFI 6. I separated all the linkages and checked each pivot etc individually. In my case the arm that goes from the bell crank at the rear of the transaxle though the engine tin was rubbing a bit. It was also too long. A little bending and better than ever. Greased everything while I was in there so good for the long haul now. That said I do feel the cable the cable itself could be smoother...

Pete

Posted by: VaccaRabite May 23 2023, 06:04 AM

If your car has carbs, your throttle link could also be binding.
You could have gunk built up at any of the points where the cable goes into the sheath.
You could have wires from the throttle cable coming loose and snagging the sheath.
You could be wrapped around the clutch.
Your throttle return spring my have come loose, or gotten weaker, and you need a second throttle return spring (common with carbs).

Lots and lots of potential reasons. Get back there and start looking!
Zach

Posted by: dr914@autoatlanta.com May 23 2023, 08:27 AM

Bad accelerator cable
bad hinge inside acc pedal
pedal cluster bushings bad
return spring missing at throttle body
accelerator cable misrouted (could be interfering with clutch cable or kinked
accelerator cable getting hot because it is being used as a ground due to bad grounds

all covered in the book 914 "tech tips 700"

QUOTE(tsvo @ May 21 2023, 04:42 AM)

Posted by: Dave_Darling May 23 2023, 12:52 PM

Isolate the problem. Unhook the throttle cable from the throttle body. Does the idle still stick? If so, the problem is in the throttle body. Clean it and carefully inspect the throttle shaft and where it goes through the throttle body.

If that isn't the issue, then hook up the cable to the throttle body and unhook it from the pedal. Does the pedal move freely and return all the way? If not, the pedal pivot is likely rusted. Pull on the throttle cable. Does it return all the way? If not, there is an issue with the cable. Check the routing (especially up in the front of the center tunnel) and condition of the cable.

--DD

Posted by: Dlee6205 May 23 2023, 01:16 PM

QUOTE(Dave_Darling @ May 23 2023, 02:52 PM)