Help with TDI 140 Avant

[Ayub97]

i have a audi a4 140 tdi /05 model.

when the car is hot the idle seems rough seem like a misfire.

also when you hold the rev speed at 1200 rpm its seems to run rough like and air leak. ( engine rocks a little/ u can feel it in the cabin)

can any one help?

i have been told this is normal.

the car drive's fine lots of power and i just have had a new EGR valve. its made no diffrence.

i've booked it in with the dealer lets hope it get sorted.

any advise?

Edited September 7, 2008 by Ayub97

[cruiser647]

Might be worth you checking for leaky pipes and also clean the MAF (very gently with a cotton bud or just spray it with carb cleaner and let it dry out!!!)?

[shark_90]

I had similar with an old PD130 A4 and the stealer diagnosed it faulty injectors and wanted to replace all 4 (yeah right!).

Other theroies were that it could either be an engine mount or the Dual Mass Flywheel.

[Ayub97]

cars been to the dealer, they told theres nothing up with it! this normal for the 2.0 tdi engine..

[BW2309]

Hi there. It is possible it's injectors. If they, or even one, becomes worn or clogged then they only tend to play up at idle as as the engine speed increases the fuel pressure does too, forcing them to function correctly. It is easy enough to check for their operation on a diagnostic computer through measured block values and if they are operating out of their safe range they will record a fault in the ECU. Make sure your fuel filter has been changed, they have a water trap inside and if this gets over full the water can contaminate the fuel. A reputable fuel aditive may be helpful to. I would suggest Forte (Forte Diesel Treatment). Its very good and actually raises the Cetane rating of the fuel. Use only good quality fuel from a branded station too - it does make a difference! You could even try Shell's V-Power Diesel or BP's Ultimate Diesel for a while. See if it helps. Failing that, does the car seem to use any coolant at all? Early 2.0TDi's had an issue with the cylinder heads going pourous and so small amounts of coolant could leak into the cylinders after the engine is stopped. That though aften causes knocking noises at initial start up to so don't panic!

[Tame Technician]

Sounds normal to me. We get that complaint alot, we had a customer try 5 different cars before he believed us.

We did find however the 140bhp B7's were a lot worse than the 170's. Customer, agreed characteristic in the end, backed the car and got a 170bhp version.

Injector seals and tandum pump can cause similar but much more noticable fault, get them to "CLAMP THE RETURN PIPE" they will know what that means, and see if it improves. If it stays the same, car is factory standard.