Overheating

[jesse_gabriel]

My a4 1.8t is overheating and I'm not really sure where to start, if I leave the car stationery and even rev the engine, it's fine but when I'm driving the temperature will shoot up very very fast probably all the way to Max in about 10 seconds but it will also go down again. It's very inconsistent, Amy ideas?

[Furly]

You can check the thermostat
Try not to drive it around if it's overheating. You'll warp the head.
how many miles on it ?

[jesse_gabriel]

165,000 miles

[andrew96]

I had a similar problem. First my waterpump then a defective thermostat. Do you still have heat?

[Kevin C]

My a4 1.8t is overheating and I'm not really sure where to start, if I leave the car stationery and even rev the engine, it's fine but when I'm driving the temperature will shoot up very very fast probably all the way to Max in about 10 seconds but it will also go down again. It's very inconsistent, Amy ideas?

A ten second temperature rise seems strange, although with the factory gauges nonlinear response, I guess its possible. I would double check to see if the motor is really getting that hot, or do you have a bad temperature sensor.

[G-Ride]

Is it spitting coolant back out through the overflow on the expansion tank at all? Any heavy pressure build up in the upper radiator hose?

[jesse_gabriel]

I haven't tried the heat but I wil tomorrow. And the engine is definitely getting hot, the first time I noticed it there was already coolant coking out of the overflow.

[Kevin C]

OEM water pump with a loose impeller?

[MikTip]

Take it to a mechanic who knows Audi and can fix.