Throttle sticking shut

[stevec205gti]

Anyone had any problems with the throttle sticking shut after the car's been left for a bit? :inquisiti

I first noticed it when I was putting the car back together, but assumed it was because the throttle hadn't been moved for about 6 months. I cleaned the butterfly and housing up in situ and it was okay. Now i'm driving it more often again, it seems to do it all the time after the engine's been left to cool - as long as you give the throttle pedal a kick before you start the engine it gives way and operates as normal, but obviously this shouldn't be the case. Anyone else experienced this, and more importantly, how did you fix it?

[Kieran]

Hmmm - butterfly was my 1st thought... Hmm. How much tension is on the throttle cable? There's a couple of bolts on the back of the inlet plenum that you loosen to adjust tension. There should be virtually no play - specification is ~1mm of slack before it opens the throttle butterfly.

You could also try to lubricate the springs on the T/B if you've not already done so?

[Nick Mann]

Is it certainly the TB and not the cable itself?

[stevec205gti]

I've done some more investigating this afternoon. There's nothing wrong with the cable as i can get that to move from inside the engine bay - it's the actual butterfly itself that's the problem. I've given the butterfly and housing a good scrub with carb cleaner and got plenty of crud off, then gave it a squirt with some WD40 to lube it a little, and you could feel it made a difference straight away. I'm not sure how long the will last though, I'll keep an eye on it. It could be that I need to put some heavier oil down around the edge of the butterfly if the WD40 keeps drying out.

[I-S]

It might be that oil could be the problem, if it's meant to be a dry area - oil will attract dirt to stick to it (although where you are talking about is behind the air filter so shouldn't be that dirty unless you use a K&N).

[Paul Beazer]

Perhaps there were some oily deposits in there when you parked up and its dried out a bit in the 6 months it was sat around, and gone a bit tarry?

[bonesthebutcher]

Anyone had any problems with the throttle sticking shut after the car's been left for a bit? :inquisiti
Did you ever get to the bottom of this? Mine has a tendency to stick shut from time to time - when it's playing up, moving in traffic is more of a "blip throttle to un-stick it, then accelerate normally".

When it gets too annoying I disconnect the air-intake pipe and give the contact surfaces where the butterfly valve sits closed a good clean with a rag soaked in carburettor cleaner. The rag generally comes out black, but the throttle no longer sticks for a good month or two. I also found that lubricating the springs and throttle cable make no difference... :sad3:

[Eurospec]

Throttle stop mate, try adjusting that a tiny little bit. The butterfly is sticking in the tb, because its moving too far. Adjusting the stop should sort you out.

Cheers,

Ben.

[Paul Beazer]

Had this on the Mrs's Mazda 323. Butterfly was a bit gunked up. Have a good wipe around there the inlet with the throttle butterfly open with a petrol soaked rag and it should sort it.

[martin_y]

Any Toyota parts in there?

[bonesthebutcher]

Any Toyota parts in there?

/haz

[bonesthebutcher]

Throttle stop mate, try adjusting that a tiny little bit. The butterfly is sticking in the tb, because its moving too far. Adjusting the stop should sort you out.

Cheers,

Ben.
Thanks for that, Ben. Adjusted it at the weekend and can happily say Wow! What a much nicer car to drive /woot2 Didn't appreciate how much I'd just got used to blipping the throttle to unstick it before rolling on the gas!

[eyeballprawn]

I'm having the same problem with the throttle sticking shut after I gave it a clean up. Originally I thought it must have been because I'd cleaned the oil off it and it needed lubricating again, but after reading this thread it seems that I should adjust the throttle stop instead.

But I have a question, how far should the butterfly actually close? There is a scalloped section in the throttle body that the butterfly closes into, but mine only closes over about 50% of this. So the butterfly never actually closes to 100% vertical. Is this correct?

[eyeballprawn]

If it's of any help, I checked things out with EvoScan and the throttle ranges from 13% when closed to 96% when fully open.

[scott.mohekey]

Any Toyota parts in there?

Can't be.. they stick open, not shut.