My 98.5 A4 2.8 Quattro has started overheating and the dealer and 2 other garages have no clue as to why this is happening. Am hoping someone on this board can shed some light on this...

In stop and go traffic the temp gauge starts to climb above the half way mark (goes up to the next notch in the scale and higher as well) and does not come back down once traffic has eased up and the car is moving at normal speed. The same thing happens if I push the car a little bit on the highway (eg: going uphill at 60mph). Also, if I go from point A to point B, then stop the car, then restart and go to point C, the temperature gauge again shows higher than normal temperature and does not come back down (it has even reached the mark just before the H mark on the gauge). This has never happened in the 3.5 years that I have owned this car. The garages can only say that its because of the heat this summer in texas and that this is normal and that the temperature should come down once the car is being driven. The problem with this explanation is that its been hotter than this in the last couple of years and I've never seen this happen.

Any suggestions as to what they can check? They have checked all the fans etc and everything checks out. The only other suggestion is that its a faulty gauge but no one is sure that thats the problem. Help!

Thanks in advance.

 

what mod's do you have?

 

First check to make sure you don't have air bubbles in your cooling system. Perhaps flush and refill also. Bubbles could throw the temp gauge off.

When you change your oil, double check that there's no water or coolant in it. That could indicate a head gasket problem, major work.

Have your thermostat checked. It may be sticking, and not allowing proper levels of coolant flow.

 

I believe it all started with the water pump. But I decided to replace the thermostat at the same time.

From what you say, check or replace your thermostat (they're pretty cheap), make sure your fan is running ok and turns on at high temps, and I would maybe get the water pump checked, although they generally don't go out that fast.

 

Thanks for the suggestions. I'll pass them on to
the dealor.

 

No mods to the car.

The max temperature I've seen this summer has been 105F.

 

And mine has never gone above halfway unless I stop the car and then restart it. But in traffic it should remain halfway. You could have a bad thermostat...it's possible the fan clutch is not working correctly as well. I'd check replace the thermostat though.

 

Apparently there are 2 fans at the front of the car and they are only working occasionally. When driving the rushing air is enough to compensate but when sitting if the fans decide to shut down the car heats up. I believe that the service team has decided that a relay is the sulprit. Not sure if the A4 has the same system though. Good luck.

 

outside, you would be amazed at how much gunk gets trapped in there, and if there is enough of it, it could severely reduce your cooling abilities. Try to spray the water from the inside of the engine bay, and also spray from the front, right into the condensor. Not too much pressure, just a regular house hose.

 

If cleaning everything out doesn't work, a shop should be able to use a IR thermometer and check for hot spots in your radiator. You might have a clog, or a warn out radiator. After a while (usually not as young as your car) the radiator will lose its ability to absorb the heat from the fluid, so you'll over heat when there isn't enough air passing thru.

Mike
'01.5 1.8TQMS