Sticking throttle ?

[WillG]

I have a standard 2002 1.6k roadsport and every now and again the revs will hang. I cannot recreate by simply reving the engine, it only seems to happen when you accelerate to high revs and then lift off. If I dip the clutch the revs hang around 4k, tapping the throttle quickly will allow the revs to drop as normal.

I changed the idle control valve for supposedly a good 2nd hand one, and the whole throttle assembly seems physically fine, everything moves freely, all reasonably clean, etc. what else should I be looking at?

Cheers

[Gingerbread Man]

This has happened to me before. I believe it was the pedals bush in the pedal box. A dismantle and resemble cured it I think.

To check, does the pedal not return fully? If you find it happening, can you put your toe under the pedal and pull the pedal up, does that stop it?

[Doug Phillips]

I had this a good few years ago, after replacing the cable and checking that the pedal was ok I was stumped. It turned out to be the air control valve on the throttle body, I took the springs of and gave them a good clean and used lots of WD40. It has been fine since.

[WillG]

Thanks guys.

Hadn't thought about checking the pedal itself, I'll do that.

Doug do you mean the idle valve on the side of the throttle? If so, when I changed this it didn't look dismantle-able? Is this what you cleaned?

Cheers

Will

[Doug Phillips]

Just had a look at the TB, there are two large springs one for the throttle cable and another on the other side which I believe is the air control valve. Mine were covered if a fine grit (and looking at them now, I should clean them again) I took them off and gave them a wash in some petrol, then sprayed any moving parts with WD40. This solved my problem.

[WillG]

Right, drove 7 yesterday, still doing it. Just had a chance to look at this properly. Everything seems physically fine, pedal is perfect, cable is smooth, no kinks, etc. Throttle body seems good too.

Disconnected it all, all works independently without any hint of any sticking in the range of movements. Greased it all up. Take it out tomorrow and see how it goes...

Doug my throttle body does not seem to be dismatlebale as pictured below (not mine, but the same) - am I missing something!?!



Cheers

Will

[Gingerbread Man]

Metal throttle body not plastic?

[Gingerbread Man]

Metal throttle body not plastic?

[WillG]

Yep. Metal throttle body.