1998 Audi A4 2.8 Quattro
210,xxx

I have a slow coolant leak and i can not figure out where its coming from. There are no puddles or drips under the car.The radiator is fine the upper and lower hose is fine, the inlet and outlets of the heater core is fine. No coolant smell inside car and the passenger carpet is not wet. Heater is blowing hot air and it is not overheating at all. The oil and coolant are not mixing. I have to top up with coolant at least once a week. Sometimes i do see steam coming off the back passenger side of the engine towards the bottom but it is very faint and i suspect the leak may be there somewhere. I attached a link to the location of where i suspect the leak to be coming from. any help?

 

any ideas?

 

Can you get a pressure test kit? I got one from autozone rental a while back to find a leaking coolant line. I paid $80 or so, did it right there in the parking lot then walked back in and returned it and got all my money back.

 

i dont even know where to start with using a pressure kit. I could try that though. any advice?

 

basically it's just a pump that you connect to the top of your reservoir. You take the cap off your reservoir and attach the pump with correct fitting to the same place. You then pump a few times and it pressurizes the whole system and you can search for leaks without having your car on.

Obviously it's smart to wipe down any wet areas so you can see what wet spots are new and go from there.

This gives you an idea. The different colored caps are for different sized reservoirs (different makes and models...)

 

Hi

I also have exactly same problem with Audi A4 1998 2.4L, can you please let me know if you resolved your issue and how.

Coolant is just lasting about 1000kms for me

 

There is a metal pipe under the intake. It has o'rings on 3 or 4 spots if I recall.
Hard to see and harder to repair.

 

I concur with smittylube. There are 5 O-rings total. Three in back and 2 up front behind the water pump area. Intake has to come off to do the job and once it's off it's still quite the project. Unless you are really familiar with this type of work, it's one case where paying a pro to do it will be worth the cost. That's just my well intentioned recommendation.

 

thank you all

 

I have had an issue with coolant leaking directly behind the valve cover and squirting on to the exhaust and running onto oil pan. i found it to be a coolant temperature sensor o ring.