Throttle sticking

[virdi325i]

Hi,

I have a S50 M3, and have a very annoying problem with it....

When the car has been driven for over half hour or so the throttle starts to stick, what happens is the car stays at high RPMs, it takes a while for the RPMs to drop (anything from 2-5 secs).

This only happens when the car is fully warmed up, it’s fine when the temps low.

Can anyone help, why this can be happening

[jonnie]

Check the routing of the throttle cable. Its most likely getting hot in one or two places and outer sleeve is making the cable stick.

[virdi325i]

Hi,

Done this already it's not the accelerator cable, the cable moves freely. they seem to get stuck when the cars hot, once the car is cooled down its fine again

[virdi325i]

This is whats happening

[jonnie]

You need to get some lubricant or grease on the spring there, that should help.

[virdi325i]

Should have mentioned before but I have tried that, cleaned all the dirt around the springs than greased all them all across.....

I even got a local mechanic to clean linkages and the butterfly flaps... still no joy.

I just don't get why it does this when the cars hot. When it’s cold is fine.

I’ll guess I’ll take it out for a long spin tomorrow and give it another greasing when the problem occurs

[Jhonno]

Bent bar? Only shows up when the heat closes up tolerances?

[virdi325i]

oh sh*t, could be the case, so can the bar it self be replaced?
What is the bar called ?

sorry for all the questions.... just want to get it sorted.

[colin325]

disconnect the cable on the bar side, try it again and if the fault occurs you can rule out the cable, looks like the throttle bar is sticking, have a gawk inside the throttle boddies if you see any sign of a black stain (carbon) clean it off. if not make sure the manifold that its bolted to or onto etc is not caught on a hose or wiring. hope it helps but as da lads said above bent bar, unless it was dropped or stood on i doubt it. make sure the return spring isn't gammy? remove it and see if da bar still does it? only doing it wen hot? your 100% sure?

[colin325]

sorry about the above comment was extremely drunk wen i posted it? its an air leak, from a breather hose or manifold rubber gasket etc. i'm nearly certain its an air leak! best of luck!

[virdi325i]

Hi Thanks for your reply, Was out in the car yesterday, and within 30 mins of the drive it started get stuck again

I have already got all deposits of carbon cleaned from the throttle boddies.



This problem only occurs when the car is hot.... as soon as the engine bay cools down the problem goes away ..... can it still be a Air Leak?