1.8t very rough idle/miss

[BL33SU]

hahhahaha i dont have a maf yay for me,

how do you run d car without as MAF? can it be done for our cars?

[99gti]

how do you run d car without as MAF? can it be done for our cars?

Haltech aftermarket ECU/computer

Yes it can also be done to your's using the oxy sensor and knock sensor to calculate the air/fuel ratio etc.

[shami]

I think he had suspension work done to his car...

Sound like MAF mate...

[DubSteve]

Dave has done something to the car lol. Didn't you have some more work other than suspension done to it, I could have sworn you told me at the BBQ.

I'm not trying to disagree with any of the mk4 owners but what about the throttle body? Maybe dirty causing these problems?

[gpk_gti]

I went through many different scenarios and fault checking when I had issues.issue 1 was a faulty 10 month old maf and a very small boost leak.But I also changed the lambda probe sensor,very hard for that to be faulty..there were no codes coming up btw.....


ive still got a spare lambda if you want.....

[Jarred]

as i've discovered recently, any small vaccum or air leak, can cause havoc, so I vote MAF, if not that O2 sensor, then depending on the work you had done, all the new joins/seals are all sealed up tight!

[Golf Loon]

Ignition control module very common on these cars. Wont show a code, or will show up as coilpack

I have a test unit if you come past. And can get you a new one lots cheaper than VW

[FknDubbin]

Haltech aftermarket ECU/computer

Yes it can also be done to your's using the oxy sensor and knock sensor to calculate the air/fuel ratio etc.

You still need to calculate the amount of air entering the engine. im guessing Haltech uses a manifold absolute pressure (MAP) sensor instead of a MAF sensor.

[JustCruisn]

I had a vacuum leak in mk mk4 and the idel was way rough. I found a hole in the pipe which runs from the throttle body round to the brake booster. A quick patch fixed this up.
Also APR chpped 1.8Ts can have a rought idle when the aircon is on, pretty common but not as rough as a leaking hose.

[torque]

Faulty maf; O2 sensors don't cause rough idle