Audi a6 2.5 tdi endine judder! Help please ???

**graemer147** · 12-05-2010,04:00 PM

Yes that is correct, When i hold the accelerator in a certain "light" position it makes the engine lumpy as though it is being starved. This is a real painful persistent problem. The 2 main driving positions 30 in 3rd/4th and 75mph in 6th and you find it juddering like mad. As i say i hope to god that this is just the fuel filter and a service that needs doing. Should you hear anything before me can you keep me posted mickmcvw! Also how long have you had the problem and did anyone tell you it might me the injector pump???

**graemer147** · 13-05-2010,10:30 AM

Hi there, Just thought i would update you on my progress. Just scanned it with vag com and i have the following fault code 00523 intake air temp sensor (G42) open or short 30-10... looks as though this may be the cause but will let you know when i replace it.

**kid-jensen** · 13-05-2010,02:28 PM

Hi,

Don't forget that the diagnosys "Open/Short" could just be the wire to it, not necessarily the sensor.....

**mickmcvw** · 31-05-2010,11:09 AM

Originally Posted by graemer147

Hi there, Just thought i would update you on my progress. Just scanned it with vag com and i have the following fault code 00523 intake air temp sensor (G42) open or short 30-10... looks as though this may be the cause but will let you know when i replace it.

Did you ever get this sorted? I thought my problem had gone away after a service about 10 days ago but the judder was back again at 2100 RPM on Friday. Seemed to go though once the engine had warmed...

**foxcupra** · 31-05-2010,04:29 PM

Try unplugged the MAF and see if the symptoms persist.

Mines a 2.7t so its different but with the MAF unplugged mine doesnt do it. With it plugged in it does it occassionly.

**macscunge** · 20-02-2011,03:57 PM

I have this slight juddering on my 1999 6 speed manual 2.5 tdi quattro. I have changed everything on my engine including the injection pump. Only thing I haven't done is glow plugs and injectors. Still have judder at low revs in every gear and can feel it in neutral. Seemed less when I blanked off egr. Glad to hear I'm not alone. Will get injectors cleaned and see what happens.

**snapdragon** · 20-02-2011,11:51 PM

I would remove the rocker covers and checked for the dreaded cam wear or thrown rockers.

**leontdi** · 24-12-2012,08:17 PM

Hi. did anyone find a common cure for these issues? my A4 quattro seems to do the same. I only notice it sometimes and in any gear upto 4th gear, 5th and 6th i dont notice anything. I have not done anything as of yet as to curing it and it is due a service in 2 months.

any ideas where to look?

again its fine throughout the rev range and pulls like a train. just the judder at about 2000 rpm.

any help very much appreciated.

James

**JohnHighfield** · 24-12-2012,09:53 PM

Hi - just an update....

The small occasional judder became the least of my worries as my gearbox started making a groaning noise..

I read all the doom & gloom reports about the problems with the CVT gearboxes & feared the worst. After going to a place in Milton Keynes (mentioned in these forums) who charged me about £50 to tell me they only fix the ECUs & not the mechanicals - I was eventually recommended, by my Audi indi, a place in Biggleswade (A1 Premier Tranmissions) who re-builds CVT gearboxes.

They diagnosed a worn crownwheel & pinion - as although I had changed the gearbox oil they said the differential oil was seperate (?) - & rebuilt my box. It wasn't cheap @ about £1,800 - but much cheaper than the £4K I was told a new box would cost.

The groan is gone & I have now had my 6 months check & all seems to be going well - so fingers crossed.

I would thoroughly recommend the guys at A1 Premier Tranmissions - and it was interesting to see that they had a large courtyard full of cars to be repaired including several Audi's - TTs included!

John

**leontdi** · 24-12-2012,10:05 PM

Thanks for the reply John. Mine is a manual gearbox model so my slight judder must be engine related. It's similar to what we used to have many 1.5 diesel renaults doing when they had injector issues. I think my first port of call is going to be a good service all filters and renew vacuum hoses and clean the egr and see how it is then. Failing that I will get it read for codes and see what they come up with. I read many issues about the fuel pump bit most of those issues seem to be that the car has had a sudden break down.

James