Accelerator / Gas Pedal Weird Behaviour

[DaveBoettcher]

I took my 1988 944S for an MOT at the weekend and the garage said that while they were moving the car around the accelerator pedal went to the floor and stayed there. They checked it all over under the bonnet and around the pedal mechanism, and lubed the mechanism, but they couldn't see anything wrong. They did check that the return spring, item 12 on the diagram, was in place, and said that there is only one way to fit it so it couldn't be wrong.

However, now when I am driving the car the accelerator pedal is behaving really strangely. For the first half of its travel it feels like normal - pushing back quite firmly against my foot as I shove it further down. But after about half way the resistance gets a lot less, it is much easier to push the pedal further down, and when I lift off the pedal is reluctant to come back up.

It doesn't feel like it is sticking, everything feels smooth and well lubed, it just feels like the spring that pulls it back is only really working during the first half of the travel. Once it gets past about half way it feels like there is much less pulling the pedal back - there is much less pressure from the pedal against my foot, and I feel I can almost lift my foot off it as it comes back, unlike the first half of the travel when the pedal is firmly pushed against my foot.

It's a weird feeling, it feels almost like a spring loaded over-centre fastener if you know what I mean - as you start to close the fastener you have to work against the spring, but once it goes over-centre the spring starts working with you.

Any ideas? Thanks guys.

Regards - David

[951S/928S]

It sounds like it is time to change your throttle cable. Take a look at the cable, between the firewall and where it attaches to the gas pedal. You will probably see some fraying wire cable, which will not allow the cable to go back into the sheathing. If you see this situation, get a new cable immediately, or you will find the throttle stuck to the floor while you are in traffic.

[emoore924]

Any Toyota parts on the car?

[924RACR]

Could be you should also look at the linkage. I have seen the throttle rod (that attaches to the plastic pedal) bent straighter, so that it does "over-cam" and lock up.

Of course, since that's RHD, things may be a little different than our cars, but I'd bet the same potential exists.

[emoore924]

In all seriousness, yep, that happened to me. The rod that's part of the linkage down by the pedal wore, it would over-rotate and the gas pedal would stick momentarily, then slap the bottom of my foot when I let off. Not confidence inspiring...