Throttle problem - Prompt advice would be much appreciated

The throttle of my 99 Corolla was feeling sort of sticky, which had happened before, so I cleaned the throttle plate & body. Afterwards, the throttle was more sticky. I could barely get it open with moderate pressure, then it would suddenly open very wide with much more pressure. I noticed that the cable that goes to what I presume is the cruise-control unit was not in its groove. When I put it in its groove, the throttle wouldn't close and the engine raced as soon as I started it.

I checked the TB again to make sure I hadn't left any bits or paper towel or anything stuck in there.

Any ideas?

Reply to
Wesley Hunt
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Remove the cables from the TB and see if one or both is stickiing, if so you a spray oil (NOT WD-40; GM sells some excellent spray)

Reply to
hachiroku

Use TB/Carb cleaner - it doesn't leave a film.

Besides what Hachiroku suggests, clean the throttle plate and body again, making sure to get both sides of the plate and the edge of the plate where it meets the body. Give it a good soaking with the carb cleaner, scrubbing with an old toothbrush if necessary and then wipe out the mess. The film that forms is pretty sticky and sometimes takes multiple cleanings. Also spray the rod that the throttle plate pivots on where it penetrates the body.

Reply to
Ray O

Upon further inspection, I have determined that it is the cruise-control box that is stopping the motion of the cable and thus preventing the throttle from closing all the way. (It was sticking closed when out of the groove.) I think the cable was out of the groove all along, and thus the cruise control is out of aligment or calibration. I don't see any obvious way of correcting it. The only thing I can think of other than getting a new cable or completely disassembling the cruise-control box and seeing if there is a way, is to put the front wheels on a dyno, put the cable in the groove (it has to start out of the groove or else the engine will redline as soon as you turn the key), and hope it will recalibrate itself. I would have to get it towed in order to do that. I suppose I could also put the front end on jackstands, but I think that would be too dangerous.

Reply to
Wesley Hunt

is it an auto?..i have a similar problem with my MR2 sw20 1991. this is an auto and there is an additional cable from the throttle housing that goes to the gearbox for the "kickdown". the cable frequently sticks, and after a firm push on the throttle it clears. ive located the problem to be inside the gearbox itself, so for now its left well alone.

Reply to
anon

Yes, but it's not the kickdown cable. The kickdown cable is slack. It's the throttle cable which runs to the cruise-control box. It is definitely the cruise-control box that is stopping the throttle from closing all the way. The other cable, which goes to the pedal, has some slack.

Reply to
Wesley Hunt

You should be able to physically disconnect the cruise control cable at the bell crank where it joins with the throttle cable.

Reply to
Ray O

I played around with what appears to be an adjustment device near the end of the throttle cable, near the throttle body, and now everything seems to be working fine. I'm not sure what I did other than detaching and re-attaching it.

Thanks for the advice.

Reply to
Wesley Hunt

You're welcome! I'm glad it worked out.

Reply to
Ray O

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