Missing in idle - major issue please help

[urban-audi]

Hi

I need help my Audi A6 (2003) 2.5 TDI model has developed a fault in that when it is in idle or low speed it is missing/rattling (juddering) the problem seems to be getting worse by the day and is very worrying.

When I accelerate above 40mph the ride becomes smooth. Which leads me to beleive that I may have a faulty injector.

I have taken it to a local mechanic and he stated that the cam belt may be at fault but after checking that.. it is clear to see that is not the problem.

I think it has something to do with the fuel delivery but I am not knowledgable on cars so would appreciate if someone can help as it is not sounding healthy at all.

Has anyone else had a similar problem and please can someone help before I fork out a fortune for someone to diagnose it!

thanks

 

[NIGEL]

Do you have an automatic box? if so have you checked the throttle cable as it may need adjusting as had same prob with mine and the idle was low sometimes and engine would stall at the lights. if you have vagcom then a fault would come up ref the throttle body. The cable adjustment is on the throttle body at the rear very fiddly to do as you have to remove a clip and have a second mechanic push the throttle all the way to the floor and then reinstall the clip and have the second mechanic push the throttle a few times and you should hear a click noise from your kickdown then road test and readjust if need be.

 

[mach1tl]

This engine had a problem with camshafts which were modified in later cars. This could be a possible avenue to follow for this engine. Either they used to crack and the lobe of the cam used to wear away, or the material was soft and again they used to wear. If the timing is ok, and the rest of the obvious things have been checked by your mechanic get the cam covers off and inspect them. The bank of the engine with the most noise is a good place to start but get both sides checked.

 

[Flying Spanner]

Do you have an automatic box? if so have you checked the throttle cable as it may need adjusting as had same prob with mine and the idle was low sometimes and engine would stall at the lights. if you have vagcom then a fault would come up ref the throttle body. The cable adjustment is on the throttle body at the rear very fiddly to do as you have to remove a clip and have a second mechanic push the throttle all the way to the floor and then reinstall the clip and have the second mechanic push the throttle a few times and you should hear a click noise from your kickdown then road test and readjust if need be.

The car has drive by wire. No throttle cable or throttle body on this.

My Allroad had the inlet cam problem. It was an 03 AKE 180 engine. As the cams wore down, the little rocker fingers dropped into the engine which gave the same problem you describe. If it is this fault DONT DRIVE any further. Get it recoverd to a specialist or centre. You will end up replacing the engine if you continue!

 

[tdi-man]

hi did you get the car sorted ?