idle problem fix

[karls s3]

i have been looking for what has been causing my idle problem , revs drop and come back up and only dose this on idle when i pull up at lights. i have tryed every thing to sort this problem

like cleaned throttle body and reset with vagcom
also cleaned injectors
changed plugs
change coil packs x4
air filter
fuel filter
lambda sensor 1 as i had vagcom fault code
and changed egt sensor as i had fault code.

all codes gone and not come back

and i found how to get the idle to stable all the time all i done is unpluged the egt sensor and took it for a drive for a few days and its fine all the time , but what damage will it do if i leave it unpluged
will the car overfuel

 

[sportquattro]

Check the vac hoses underneath the inlet manifold, mine had the same problem and this was the cause.

 

[karls s3]

Check them mate one had split so had to repair with silicone .

 

[Alex C]

cant be good driving around with the EGT unplugged. I am pretty sure will overfuel and you will loose power too. Your not considering driving it from now on with the EGT unplugged are you? Does the EML light not come on with the EGT unplugged?

 

[Dani_B19]

Ive got the same problem. All vac lines replaced etc and nothings work! Dont think mines got a egt sensor as its a apy engine. Any ideas would be good!

 

[karls s3]

no pluged it back in and no eml light came on.

 

[karls s3]

If i hold the rev to 1000 rpm i get a popin from exhaust like its a slight miss fire i have tried disconnecting the maf and made no difference and brought on the tc light until i plug it in again

 

[Gavin G]

Faulty MAF?

 

[karls s3]

I un plug the maf made no difference

 

[beachbuggy]

I going to take a wild stab here as it sounds like you've already looked at the easy things.

It sounds like especially with the poppin, that you have a leak in the inlet gasket or injector bungs. Drawing in etc air and causing the idle problems at misfires.

Easy way to check and I used to use this on Dellorto carbs, is to spray WD40 around the inlet and injectors, covering well the area. If the problem goes away you have a leak from either the inlet gasket or injector bung, which are common to go.

Worth a try.

 

[karls s3]

Good shout ill give that a try cheers ill order some new bungs and inlet gasket

 

[Sandip]

After changing the lambda has the fault gone or is it still there

 

[karls s3]

Gone mate had a fault for egt sensor as well and new parts been fitted and no fault codes since part fitted

 

[Sandip]

MAP sensor maybe??

 

[karls s3]

But will i get a fault code with map sensor if faulty

 

[beachbuggy]

And map sensor is for boost not vaccuum as you get at idle!

 

[vanilla_ice]

Good shout ill give that a try cheers ill order some new bungs and inlet gasket

Is that the plastic seat in the inlet manifold the injector seals sit in? Have you got part numbers and prices?

 

[karls s3]

my maf plug only has four pins and the sensor has 5 and the plastic around pins is a bit broken

 

[IbanezDan51]

my maf plug only has four pins and the sensor has 5 and the plastic around pins is a bit broken

Did you ever fix this? Im having exactly the same problem...