Failed Throttle Linkage

[HarryD]

I was doing an HPDE at The Ridge Motorsports Park in Shelton, Washington which is a few hour drive from my home.

On my second session, things were going great and all of a sudden I have NO throttle. My foot went to the floor, I felt no resistance and the car just kept slowing down. I was able to get the car safely off of the line and they black flagged the session to tow me off.

I jacked up the car and verified that all of the bell cranks I could see front to back were intact (I removed the pedal board to look behind the gas pedal). I pulled the hand brake, heater control, hand throttle assembly to see if there was something there. In the process I dropped the little hand throttle collar (Parts 90 and 91) into the tunnel (arrrrgh). I pulled the rear inspection plate in front of the rear seats. Nothing appeared out of place. I had some one step on the accelerator pedal and notice that everything up the little bellows under the car (and over the transmission mount) moved. Nothing from the bellows to the throttle body moved. After much fiddling around, it was apparent that something in the bellow was broken.

I disconnected the bell cranks at the accelerator pedal and outside of the motor (part number 11). I pulled the bellows off the car and found the broken piece. Part number 10 on this drawing.



It had separated into two pieces.





Being I need to be able to get my car home, I figured I needed a quick fix. Fortunately, AR Motorsports (Portland Oregon) was on site for driver support and emergency repairs. I showed them the two parts and how I needed to make them one. I asked if they had some safety wire so I can hold the two parts together. They said they did so I did that "arts and crafts" project.



I reassembled the car to a drivable state. I then drove carefully home (no abrupt accelerator movements).

Made it safely home. I was able to source a new coupling from my FLAPS with delivery the next day. It arrives as promised. Note the new part has the rubber encased on a metal sleeve to keep the ends from separating from the body.



I disassemble throttle linkage to install the new part. After several hours of "fun", good news, throttle linkage works again!

Bad news, I was unable to retrieve the hand throttle collar and longer have a working hand throttle. Also, at this point in time, I am stymied by how to get the linkage bellows (part 12) back on the opening to the tunnel on the car. These items will need to be addressed on a later day.

[911obgyn]

Nice Macguiver!
What year car? Now i have something else to worry about.

[HarryD]

Originally Posted by 911obgyn

Nice Macguiver!
What year car? Now i have something else to worry about.

Thanks. Beat a long tow home.

Car year is in my signature line. 1973.5.

Not a hard fix. Glad they have the part.

[PeteKz]

Re the hand throttle: If you haven't replaced the plastic parts in the tunnel yet, they almost certainly are deteriorated and falling apart. I lost my hand throttle had to replace those parts about 4 years ago due to age deterioration. You have to remove the hand brake assembly to get at these pieces, and work carefully down through that hole in the tunnel. I recall it was not a lot of fun. If you haven't replaced the shift rod bushings, do those at the same time. They are made of the same material and also aging out.

[HarryD]

Originally Posted by PeteKz

Re the hand throttle: If you haven't replaced the plastic parts in the tunnel yet, they almost certainly are deteriorated and falling apart. I lost my hand throttle had to replace those parts about 4 years ago due to age deterioration. You have to remove the hand brake assembly to get at these pieces, and work carefully down through that hole in the tunnel. I recall it was not a lot of fun. If you haven't replaced the shift rod bushings, do those at the same time. They are made of the same material and also aging out.

I replaced the hand throttle chunk a few years ago so that is good. Not sure if I will tackle the throttle bushes (part 13).

[Das86TurboII]

Timely post. This just happened to me, though enroute to a concert. Towed it home. Made concert, late. I’ve yet to tear into it. Question. Can you attach a pdf of the schematic with part numbers? TIA.

[HarryD]

Originally Posted by Das86TurboII

Timely post. This just happened to me, though enroute to a concert. Towed it home. Made concert, late. I’ve yet to tear into it. Question. Can you attach a pdf of the schematic with part numbers? TIA.

In post 1 it is part 10. The part number for the broken part is in the picture of the replacement part.

To help your self, get the Factory Parts Manual (aka PET) for your car here:

https://www.porsche.com/usa/accessoriesandservices/classic/genuineparts/originalpartscatalogue/

[EC900]

Nice handy on-the-fly repair. +1 on replacing all the plastic-type tunnel bushings, 40-50 yrs of petroleum based lubricants basically dissolves them.
You may need to assemble the entire or most of the throttle rod components and then insert it back in sections, or McGiver a length of that wire with a hook on the end thru the boot and maybe pull/slide it over ?
What were they thinkin’…..wouldn’t it have be nice if designed a structural “lid or access panel” for the tunnel? My, my.

- I replaced #13 (all 3) wasn’t difficult at all. They’re split and slide onto the cable, re-bend the folding tabs in the tunnel wall and they stay in place. Of course, removing passenger seat makes the job that much easier and to remove the handbrake for even better access.

[HarryD]

FWIW I needed to remove the shifter to get access to one of the bushes as well