Snapped off sensor??

[Koose]

Hey guys

My gti 16v just failed on emmissions, we noticed a sensor hanging off dangling behind the engine, it looks to be  a switch or sensor of somesort its the one squared in this box:



Does any knowledgable chap know what its snapped/come off of, and if it would cause the car to run rich and be slow as hell?

[Leon27]

That's the idle switch, it doesn't help that it's hanging off and in theory at idle the Idle Valve (ISV) may not be active so could be causing emmision related faults.

It comes with that plate you see so is that bolt missing?

Also check the wiring that goes to the connector to the idle switch as it runs above the exhaust manifold and can sometimes melt/get burnt causing all sorts of running issues. This wiring also goes to the Throttle position switch which could cause your car to be slow.

I'd get the switch back on, set it up, then see how you get on with regards to the performace. If it's still slow then scan the car for faults

[Koose]

Youre a gent and a scholar. With your help and the picture, its now able tied to said bracket whilst the glue sets and the car now runs better and idles much better.
Still feels slower than id expect a golf gti 16v to be if the figures ive got of 150hp and 1035kilos are correct? Maybe it just doesnt feel quicker, i dunno. Bring on the mot and some gentle fettling.

[Leon27]

When I first bought mine I didn't think it was fast at all but after replacing a load of parts it's where I think it should be.
Problem is with the ABF engine it can run with some dead or unplugged sensors and you'd never know because the engine light doesn't come on like with the newer cars!
Give it a good service and look at the air filter, leads, plugs, rotor arm and cap, if they haven't been done already. If it hasn't it will hopefully increase your mpg if not bhp as well

[Koose]

Thanks mate.  I really hope so , id heard mk3 and 4 GTis werent fast but i thought it was the 8v and the non turbo mk4 people were talking about. Ive seen book figures of 7.5 seconds 0-60 and 135mph top end for the abf mk3 but mine is nowhere near that id hope for 12seconds and 110. Trouble is i cant get to a bloody garage as im working 6 days a week 8am till 7pm. Had mot and failed on emmissions but they didnt have a courtesy car as promised so i didnt have time for the diagnostics.

[Screech16v]

They arn't rocket ship fast but are nippy if running well and driven correctly