Kalahati

I had put my Allroad in the garage to get the timing done as well as the pulleys and such. It is an Allroad 2003 2.5 TDI AKE Automatic.

After the car was put back together, there are now some unpleasant symptoms which the garage has no idea about.

The car starts and idle fine in Neutral but there is now an audible nose from the intake. It's a thumping noise which is intermittent as the engine turns. As you slowly remove each part of the intake, the thumping gets louder.

The second symptom is that when the car is put in to either 'D' or 'R', the RPM seems to bounce from 800 - 950 or thereabouts. All you can hear is the revs bouncing Vroo..Vroo..Vroo.

I asked him what he thinks it is, he said he doesn't know. He said he will do some compression tests when he gets in the tools.

I suggested maybe the timing is out a tooth as they used tipex rather than timeed from scratch with the appropriate tools. Also, I noticed that they decided not to put back the AC belt on and that the whole from of the car is misaligned as the head lights do not fit flush with the rest of the car, as well as the silver trim below the headlights being snapped or as various nuts and bolts which haven't found their way back to it's original location.

Help me please.

GTA_Driver

Not sure what kid of help you're looking for, sounds like you need to take it up with the garage.

Also seems you took it to the wrong garage. One always should use timing tools.

You may need to perform a throttle Body Alignment. Google it up, there is a procedure on Ross-Tech's site. Vag-com required. This should fix the idle issue.

P4Ring

Not familiar with the 2.5 TDI as we do not get this engine here in USA but I can tell you this, YOU CHOOSE THE WRONG MECHANIC. The way it seems, precision work was not done. Leaving screws or bolts out and failure to correctly align the headlight and/or other body parts back to how Audi assembles it... or how they found it is a sign of poor workmanship. If you take the car there with your AC belt on, why would they not re-install it back...(they apparently remove it)

As mention by GTA Driver, re-calibrate the throttle body. (VAG COM/VCDS or equivalent needed)

However, I do not think this is your problem. If the car idle fine in neutral, this should't be a calibration issue. Also I am not sure what you mean removing the intake.

On Audi gasoline engines, the throttle body uses a stepper motor to move the butterfly/valve and thus control the idle speed. On drive-by-wire cars, the stepper motor controls complete movement of the valve. The exact proportion of how much air is allowed in is set by the ECU and control the idle speed and drive-ability. Programming can be lost if the battery is disconnected for extended period of time or if the gap between the throttle butterfly/valve is reduced due to dirt built up.

If programming cannot be done, clean throttle body and try again.

On looking on the 2.5 TDI from the top, I can see two wire harness on the throttle body so you may have a similar setup. Also have someone else recheck the engine timing to see if it was done properly. Check vacuum lines also.

mike sharples

does sound like they cocked up good style, i have worked on diesels for years and you DO NOT USE TIPEX.....sounds like they got the timing out one tooth and the valves are hitting, possibly now bent, requiring cyl head off, new valves and guides. I its one tooth out I have seen lots run like this and cause no damage, unless its driven, then they get damaged, two teeth out, definatly damaged. The problem is, the tension the belt wrong, the timing moves as the belt is tensioned...sounds like a bunch of idiots.....good luck, sounds like you will need it

allroad'n

back when i swapped motors in my old honda. when i first got it in, my rpms would surge like your describing. it turned out to be a bad throttle position sensor. maybe something to look into

Kalahati

An update for you guys.

I asked the guys to remove the cam cover on the left bank just to make sure there was no cam wear.

To my surprise a number of rocker arms and thrust pads had fallen out of position, even though the cam-shaft is safe and secure in it's place. The rough running was down to a number of valves not actually opening due to no rocker arms between the cam lobe and the hydraulic lifters.

Upon closer inspection I noticed the helical gears between the 2 cam shafts had broken teeth. I cannot explain this phenomenon other than coming to the conclusion that they've either timed the engine incorrectly or over-revved it beyond the limit. However, assuming it isn't their fault, perhaps it could be down to faulty hydraulic lifters, you can be the judge of this.

The cam wear was very minimal, no more than 1mm on a few selective cam lobes. They do need changing but it doesn't seem detrimental at the moment.

Opinions?

Regards.