Engine lumpy & vibrates at tickover

[chuffy]

I've had my A4 Avant 1.9 TDI Quattro for 3yrs now and only have one complaint. At tickover (correct rpm) the engine shakes, making the exhaust rattle, you only have to breathe on the accelerator and the engine smooths out perfectly.

My dealer says they cannot raise the tickover 25rpm (that's all it needs) because the engine management system will fight it. They have suggested it may be the engine mountings and have quoted £350 to replace, but cannot guarantee a cure.

Has anyone any ideas please, I do not want to spend £350 and find the problem persists.

Thanks Andy (Macclesfield)

 

[inigoj]

The only time that i have experienced the symptoms you describe is when i had a slight blow in the exhaust (mid joining collar)

Resting my foot on the accelerator was enough to stop the vibration/lumpiness.

 

[Beef]

Hi,

I have the same on my '97 1.9TDI Quattro. I did change the engine mounts and gearbox mount but this made the problem a bit worse.

A friend of mine who knows a lot about Audi's says it's the flywheel vibrating due to age....now that would be expensive to replace! (So I just live with it).

I find the problem is much reduced in warm weather - roll on the summer!

Cheers,


Beef

 

[jcb]

if your mounts are shot, get some silicon sealant and squirt it into the mounts, wait for it to harden and hey presto, new mounts!.

unlikely to be the problem though. they don't stop you engine vibrating, they just stop you feeling it in the back seat!

does it go away when the engine is warm?
Old deisels do have a habit of being a bit agrigultural until they warm up

 

[inigoj]

If your engine is not idling at 900, and it vibrates untill you touch the pedal, there is a problem, either a leak or a blockage.

Try the usual things.

Clean MAF

Clean EGR

Check vacuum hoses & intercooler.

Noisy injector

Fuel & air filters etc

Some of the cheaper tuning boxes may raise your fueling on idle, this would make the vibration go away.