Juddering Under Boost

[gregoire102]

Well!!!

When putting the car under load throughout the gears it gives a fast judder, sort of like it is misfiring.
Rev out of gear and all is good.

Just changed the MAF as this was showing as faulty so the garage changed this out last week.
While it has slightly improved the juddering is still there.

It was in for an alternator replacement before this started and wondering if anyone has knowledge on that are and what is involved, I am not sure if the engine must be raised to get the alternator and if so what may have been disconnected and possible put back wrong!!

Thanks for any help.....

 

[scotty_24]

Need to read codes from vag com.
Sounds like a miss under load / boost.
Possible plugs, plug gap, coup pack etc etc
Get the codes read and post them up

 

[Tj 0785]

No you don't have to do anything to the engine to change the alternator just need to remove the charge pipe( and this can't be put on wrong way)Have you scanned it for fault codes could be faulty coil pack

 

[Stuart B]

have you managed to get a flashing EML yet? it doesn't all the time for a misfire - I really struggled to get a fault code when mine was misfiring under load, in the end it turned out to be spark plugs - they had only done 2000 miles.

 

[GRELA]

I've got the same issue on the S3 i've just bought, plugged it in and got both lamba sensors out, G62 coolant temp sensor and EGT sensor. Cuts out power when applying full throttle and then it will finally pick up but then judder and go away at certain rpm and if i take it easy on the throttle and then boot it then it goes like a rocket with no judder or missfire.

Best bet is to plug it in.

 

[gregoire102]

Need to read codes from vag com.
Sounds like a miss under load / boost.
Possible plugs, plug gap, coup pack etc etc
Get the codes read and post them up

Cheers.
I did have the MAF fitted last week and he told me everything running as should when he hooked it up.
Hope he checked for codes, presuming he did!!

 

[gregoire102]

have you managed to get a flashing EML yet? it doesn't all the time for a misfire - I really struggled to get a fault code when mine was misfiring under load, in the end it turned out to be spark plugs - they had only done 2000 miles.

No warnings, nothing showing - I have just ordered plugs so will try that!!

 

[gregoire102]

240 horses going to waste!!! Will try plugs and hopefully get her back to full fun!!!

Thanks for reply's

 

[gregoire102]

Changed plugs this evening and not too far off perfect.
Still slight Judders at different revs and loads but so so much better!!