Throttle sticking again! Help!

[cosmoyogiman]

Hi Everyone,

Over a year ago a buttload of beach sand blew in through my radiator grill and got all over everything. Right after that my throttle started sticking. This was scary so I rebuilt my throttle body (replacing all gaskets, o-rings, and cleaning everything good). This didn't really help much so I replace the throttle return spring with a much stronger one which returned the pedal but made it really hard to press the gas pedal and made it move in a very unsmooth way like all or nothing. In the last week the throttle has been sticking more. Sometimes when I stop at a light It is hard to brake because the brakes are fighting the sticking throttle. A couple of times that even killed the engine. I have been manually returning the gas pedal with my foot more and more. So...

...HERE IS MY QUESTION: Do any of you know how I can fix this without getting a new $400 throttle body? A napa guy told my it could be the bushings on the throttle plate, but I am not sure what he is talking about .

Thanks.

[maximus7001]

I have had worn bushings on a carb make the throttle plates bind in their bores. In your case I would think that sand has gotten into something else making it stick. Heavier return springs will quickly wear the said bushings but since the heavier spring was done after the sticking I would not think that would be the problem.

An old school mechanics trick is to regularly oil the bushings where the shaft goes through with fresh 80w90 gear oil. This slows down further wear and helps plug the vacuum leak caused by the wear.

I would look elsewhere like the throttle cable and so forth for the sticking problem.

One car I had with a sticking throttle turned out to be the block heater cord was catching the throttle cable and making it stick.


Also you need to put the peticulars of your van into your profile so we know which year out of the 20 model years your van is.

[cosmoyogiman]

Thanks maximus, I will think about your tips. I did replace the cable and housing so it is not that. I can't find anything else it could be. I didn't realize the wear could cause a vacuum leak

[cowboydan]

could be your kick down cable. did you replace that also?

[Big_kid]

Gotta isolate it further- throttle butterfly, linkage, or cable?

[cosmoyogiman]

I believe the throttle cable is the same thing as the "kickdown" cable.

[Big_kid]

Throttle cable goes from the gas pedal to the throttle butterfly linkage. Kickdown cable (proper name detent cable) goes to the transmission for passing gear.

[Matrixx]

My guess would be sand in the throttle cable or kick down cable. Have a look at them first before dropping anymore money into it.

[cosmoyogiman]

Ya, I am pretty sure I replaced both cables and housings.

[jeff's93astro]

i agree with it being one of the cables. I've had over 5 vehicles with TBI all over 200k miles and none of the throttle bodies ever stuck. Not saying it aint your TBI but i'd say more unlikely

[Matrixx]

One thing about throttle cables, is they are very easily damaged, and it doesn't take much to bind them up (like sand).

Just some food for thought to think about and maybe reconsider looking at them again to make certain.

[cowboydan]

maybe it's the pedal pivot point. it doesn't happen very often but some pedals have plastic bushings that could have cracked or broke. there are only so many things connected to the gas pedal that could make it stick. are you sure your van is idling right? maybe it is stuck in high idle. when you shift into drive, it will set into gear hard and want to go. but that is mostly related to carbs and electric/vaccum chokes. if messing around with the gas pedal works to fix the idle, then your problem will be from the pedal to the cables, to the throttle linkage.... not much else to play with. by pulling back on your gas pedal, it will only go back to the preset tension and no more.

[cosmoyogiman]

Okay, I finally got a chance to check it out after all the suggestions. I found minimal friction in the throttle cable when I detached it from the butterfly, but when I put a load on it by pressing the pedal while pulling on the free other end, I found a huge amount of friction, specifically the uneven kind I usually feel while driving. So I squirted a bunch of liquid wrench dry lube in the throttle cable housing and the friction lessened some. Then I figured the binding under tension must be caused by too sharp of a bend in the cable somewhere. Sure enough, I lessened the bend of the cable just before it comes out of the housing and connects to the butterfly, and the friction lessened even more. A test drive proved that the pedal now seems to be returning fully. Not perfect, but probably not dangerous anymore.

Thanks everyone very much once again. You saved me from replacing the throttle body ($400) and that wouldn't have fixed the problem .

[cowboydan]

Okay, I finally got a chance to check it out after all the suggestions. I found minimal friction in the throttle cable when I detached it from the butterfly, but when I put a load on it by pressing the pedal while pulling on the free other end, I found a huge amount of friction, specifically the uneven kind I usually feel while driving. So I squirted a bunch of liquid wrench dry lube in the throttle cable housing and the friction lessened some. Then I figured the binding under tension must be caused by too sharp of a bend in the cable somewhere. Sure enough, I lessened the bend of the cable just before it comes out of the housing and connects to the butterfly, and the friction lessened even more. A test drive proved that the pedal now seems to be returning fully. Not perfect, but probably not dangerous anymore.

Thanks everyone very much once again. You saved me from replacing the throttle body ($400) and that wouldn't have fixed the problem .

thought you replaced it?? i would replace it again. that kink is where it will break next. it's like i any cable with a sheeth. it will rub and rub untill it breaks

[Big_kid]

Glad we could help, that's one of the things we're here for. I'm with Dan on replacing it again. Maybe not immediately, but at the next opportune time. If it's binding at all it's still not right. A pinched cable will bend at that point again if it's stressed. MAYBE put a splint on the outside of the outer cable. Also- good move on using DRY lube on it. Any petroleum based lube would have gummed it back up again.

[cosmoyogiman]

Yes, Dan, I thought I replaced it. Yesterday I confirmed that I had replaced it. The problem was that when I put the new one in I made it too short and that is why the bend was too acute and that is what caused the friction. I don't believe there is a kink in the cable, but I am going to replace the cable and housing anyway.

Kid, I like the idea of a splint. Thanks.

[JuneauCabbie]

In addition cleaning the throttle body and replacing the throttle cable, I also had to replace the cruise control cable before the sticking problem was fixed on my '01 Astro.

Fortunately, the current '03 Safari hasn't had any problems like that.

[cosmoyogiman]

Ok, so I finally replaced the throttle cable again and this time it worked! The friction is gone and I was able to put a normal strength return spring on. Now to fix a broken engine mount I just found.

[cowboydan]

Ok, so I finally replaced the throttle cable again and this time it worked! The friction is gone and I was able to put a normal strength return spring on. Now to fix a broken engine mount I just found.

don't do just one. good to here. now no more dragracing in the sand!...lol