Sticking throttle.

[pete]

After my success with the funny noise from the back (new shocks, car off rad for 10 days). And the other funny noise (new wheel bearing, car off road for 2 weeks). I am buoyed with confidnece in my mechaincing abilities.

So the throttle sticks, the car idles at 1500rpm and doesn't exactly drop quickly to that, make going down through the gears a lot less satisfying. Any ideas (K series '03 111s standard).

Pete

PS my friends '99 S1 seems to be displaying the same symptoms.

[mac]

It will be you IACV playing up - it's attached to the side of the plenium with 4 torx screws - unplug, unscrew and give it a blast with some carb cleaner.

Stick it all back together again and you should be sorted


Mac

[BiggestNizzy]

That would be my job for the day along with

find rattle
repair rattle
fit undertray
wash

[pete]

It will be you IACV playing up - it's attached to the side of the plenium with 4 torx screws - unplug, unscrew and give it a blast with some carb cleaner.

Stick it all back together again and you should be sorted


Mac

Cheers mac, (although there is a distinct chance that I didn't understand all the words in your first sentence. Specifically IACV and plenum. An is carb cleaner the same a WD40? )

[mac]

Plenium (noun) opposite of a vaccum. AKA Black plastic thing that the throttle is attached to (engine side) - maybe metalic in 111s versions)

IACV - wee thing stuck on the side of the plenium - between the plenium and the head - black plastic - has a hose coming out one end and wires out the other end - It regulates the amount of air into the engine when the butterfly valve in the throttle is closed.


Carb Cleaner - Isn't the same as WD40 - it's a blend of chemicals used to clean deposit of combustion items.


HTH


Mac

[BiggestNizzy]

the metal tubey bit to the left of the ally boxy thing at the back of the engine

[robin]

You can verify whether or not the IACV is at fault quite easily without dismantling. Let the car idle when hot. If the idle speed is too high (which yours probably is), disconnect the bypass hose that feeds the plenum and put your thumb over it - your thumb will get sucked into the pipe a bit and then that will close off the air flow. If the engine now stalls, your IACV was open too far. If the engine keeps running, especially if it keeps running at an accelerated idle speed then you have a vacuum leak elsewhere. Now refit the bypass pipe and remove the main air trunk to the throttle body (bendy pipe that goes from throttle body to airbox on the left of engine bay). Place your hand over the throttle body air intake - it will get sucked in and then the engine should stall (no air) - if the engine keeps running, your vacuum leak is elsewhere in the plenum/intake manifold.

Cheers,
Robin

[pete]

That would be my job for the day along with

find rattle
repair rattle
fit undertray
wash

Spanner and sponges (although I don't actually wash cars so just spanners) tomorrow afternoon?

[pete]

You can verify whether or not the IACV is at fault quite easily without dismantling. Let the car idle when hot. If the idle speed is too high (which yours probably is), disconnect the bypass hose that feeds the plenum and put your thumb over it - your thumb will get sucked into the pipe a bit and then that will close off the air flow. If the engine now stalls, your IACV was open too far. If the engine keeps running, especially if it keeps running at an accelerated idle speed then you have a vacuum leak elsewhere. Now refit the bypass pipe and remove the main air trunk to the throttle body (bendy pipe that goes from throttle body to airbox on the left of engine bay). Place your hand over the throttle body air intake - it will get sucked in and then the engine should stall (no air) - if the engine keeps running, your vacuum leak is elsewhere in the plenum/intake manifold.

Cheers,
Robin

Thanks will try tomorrow.

(I fear one day waking up, probably with a bit of a headache and a sense that something somewhere is terribly wrong, to find I have followed Robin's instructions and ended up completely dismantling my car. If Robin were to turn to evil he could easily turn my car into worthless scrap with a few misleading instructions and a malicious torque setting or two.)

[campbell]

(I fear one day waking up, probably with a bit of a headache and a sense that something somewhere is terribly wrong, to find I have followed Robin's instructions and ended up completely dismantling my car. If Robin were to turn to evil he could easily turn my car into worthless scrap with a few misleading instructions and a malicious torque setting or two.)

LOL!

Know what you mean Pete.

However, if Robin were to turn then I think there would already be a lot wrong with society and the world and the risks to your car would by then be the least of your worries...!

All hail the spanners. Good luck. I stuck to sponges this weekend, however. The Golf nearly had a fit, it hasn't seen the soapy side of a sponge since probably mid-summer if it's lucky. The Elise merely smirked and presumably muttered under its breath "yeah fat lot of use that is mate when all you do these days is drive me up and down the filthy M9 to work, sheesh"

What it doesn't know yet is the hardtop refitting is near, which means much snugness for the winter months. Maybe that will cheer it up again.