Troublesome s4

I recently bought a 2003 S4 and initially it was great fun, just a couple of faults. The airbag light would come on after 9 minutes and the air con wasn't working.

fixed the airbag light - a new module was needed as the old one would not code to the replacement instrument cluster. Gassed up the air con but it all leaked out again :-(. Seems like I have a leak so replaced all of the o rings at the condenser and pump but still won' t stay pressurised. Looks like a pump is needed at huge expense!

then noticed that the upper control arms were shot. Easy job I thought but the pinch bolt was well and truly seized. Even heating with oxy torch would not budge them. So I gave in and bought a pair of used uprights and put them on. Trouble is my old wheel bearings were also seized - 3 out of 4 bolts either side came out the other rounded. All put back together so took it to get it tracked - the track rod end is seized in the track arm. So now I have to replace both but of course the track rod will not come away from the rack. To cap it all on a test drive the traction control light keeps flashing and cuts the engine even at low speeds so looks like an abs sensor has been damaged during the swap.

Getting concerned that this is a problem car and 1 thing will just lead to another...

Well I have finally managed to get the car back on the road - replaced the track rods and track rod ends and put anti-seize on everything. Hopefully if/when it needs to come apart again it will be easier. The 'new' uprights had wheel bearings already fitted but I think mine are better so will be swapping them over if/when I can get the bolts outs as one on each wheel bearing has rounded.

Seems to drive better but still not happy with the steering so I suspect I will be doing the lower arms as well soon as I still get a bit of a 'clonk'. Next major job is the air con as this doesn't work. I suspect the pump but need to diagnose this better - I know I have a leak but not sure where as replaced the O rings at the condenser, receiver and pump. Odd thing is I have no fault codes logged now (from the HVACS anyway!) but I would swear that the air coming out of the blower is hotter than ambient. I have already checked the 3 flap motors on the passenger side but I have now seen that there is another on the drivers side which is related to the temperature control so I'll take a look at that also.

Trouble is the car is sooo fast that I want to try and fix the issues. It actually hasn't cost that much so far. It's just the time and frustration involved when one job results in another and then another...

dualmono21 said:

as regards the air con
check underneath the car to see if the driveshaft for the compressor is spinning properly
its powered directly off one of the sprockets on the timing gear and is designed to fail if theres a problem

its also common for the actual gearing to wear or strip teeth on the drive gear and the only way to replace this is engine out and replace the entire chain assembly ... very very expensive

Click to expand...

I've started another thread for the aircon specifically but thought I would reply here also. I think that the shaft is turning - assuming I was looking at the right bit. It was a shaft on the near side bottom front of the engine. I still think that there is another problem though as surely the fan should be on at low speed when-ever the aircon is on. No movement from the aircon fan at all.