3.2 914 throttle question

[Marv's3.2six]

Hey you guys with motronic 3.2's in your teeners.
I have this problem that seems like there is very little control of a "just off idle" throttle application, like its pulling to much cable too fast and modulation of the throttle under 2000rpm is very tricky, almost non existant. This makes the car a bit of a hand full to drive.
Is there a fix for this? Does the 80's Carrera throttle pedal assembly pull at a different ratio? Any help is appreciated.

[Buck toenges]

My throttle cable set up came from patrick motorsports. It has a black hanger off the top right transaxle /engine nut. I am having no trouble idling properly. I am using a maf now but even with the original chip airbox set up I had no problems idling. My problem is the throttle pedal sticks as I push down the pedal hard. I am going to look at the line to see where it hangs up.

[Marv's3.2six]

Buck........thanks for the response.

My car idles fine, but when you press the accelerator it jumps to 2000 rpm or above, there is virtually no modulation of the throttle below that, its either idle or over 2k. I will check into the patrick motorsports setup you mention.

I too have the MAF setup, Autothority w/chip, incredible difference in performance! I actually feel that the MAF has exasperated the throttle problem. The stock AFM had a lag in operation whereas the MAF throtlle response is instantanious.

[Dave at Pelican Parts]

Pelican also sells a bolt-on "near-OEM" throttle cable setup. Not sure if that would do anything for your throttle modulation or not, though.

Rich Johnson sells a replica OEM setup, including the need for the ($$) 914-6 throttle cable and the need to drill a boss on the intermediate plate in the transmission. You can email him at a914guy (at) aol (dot-com).

--DD

[fetus]

I also have the near-oem setup that does not require the special intermediate plate.
My 3.2 is a stock Euro 3.2 with the DME. I do not have any idle or surging problems. It sounds like you have a fuel injection problem or a vacuum leak. I can't picture the throttle cable causing your problem.

Steve

[ss6]

I also have the Patrick M/S cable (stock AFM), and have no idle issues. My cable also stuck at high throttle, here is what I learned:

The coupling hardware of both the throttle and clutch cables are quite close together where they hook up to the pedal cluster. If my throttle cable is a little loose, the coupling sags just enough (usually on the tail end of "punching" the throttle) to catch on something, probably the clutch coupling, and you get a real surprise if you punch the throttle.

Solve it by tightening the throttle cable takeup. Gotta play with it so you're just to the point that tightening any more would pull the engine off idle.

On the original throttle "jump" issue - how "stiff" is your pedal travel? I had to remove one of the two throttle return springs on mine to make the pedal easier to "feather", particularly during "heel / toe" maneuvers.

[Dave at Pelican Parts]

Hmmm.... Could the problem be in the pedal itself? The hinge inside the rubber pedal frequently starts to rust and gets "sticky" from that. Particularly if the master cylinder has ever leaked brake fluid into the footwell. (Look for rust on the floorboard or newer paint in that area for an indication that this has happened in the past.)

--DD

[Marv's3.2six]

Dave, great idea!
Thanks for the idea, from my memory there appears to be a little surface discoloration but not rust. I will check tonight to see if the pedal itself is sticky, Hmm, a little squirt squirt of WD could be the fix!?

[scg]

The metal is inside the rubber. My old one had that nice crackly crunch when I floored it.

If it is rusty, have fun getting those bolts out...

[Marv's3.2six]

My findings from Daves tip:
Pedal action good free moving, no rust. However I found a couple of things.

It appears that one of the return springs is possibly the wrong spec, (too short). It is the one that pulls the armature linkage at the throttle body closed, with the throttle in its unoperated or closed position this spring is past its maximum extension, when the throttle is opened the spring gets pretty distorted shape wise, and that can't be good for it.

The other thing I found is if I remove that spring I just mentioned and operate the throttle, under even pressure from my foot the action of the cable feels slightly "notchy" thru its range of motion, its not smooth.

Can the cable be lubed? What do you guys think? Thanks again.

[Marv's3.2six]

Driveability greatly improved by shortening up the mounting of the return spring.

My mechanic buddy sez that the teflon liner in the throttle cable tube thingy probably needs replacing for the notchy to go away.

Thanks for your help guys.