sbmellen

So, recently the coolant temperature gauge has regularly exceeded the top-dead-center mark (12 o'clock) on my '98.5 A4 (2.8 V6). With city driving, it is just a little bit beyond the center mark, but on a long drive to Mexico this w/e, it wavered anywhere from center to the next mark to the right.

Coolant level is fine (between min and max). Coolant is maybe a year old, G12. Water pump was replaced during timing belt replacement, about 3 years ago or so, at around 65,000 miles. Car is currently at 118,000.

Could it be that the thermostat is opening, but not completely? Or is this the tell-tale signs of water pump impeller about to go?

Thanks for any insight.

4Driver4

If you still have elevated temp with the new sensor, the next step would be the t-stat. If it's the t-stat, I'd probably just do a full timing belt service.

Reggie

<center><img src="http://pictureposter.audiworld.com/102/dsc01333.jpg"></center><p>And the t-sat should have been done with the t-belt.
You are close to doing it again anyway.

I suspect the fans are not the issue because at speed you do not need them with the air flow through the radiator.

This one failed just the opposite @ ~101K miles - and was not changed with the tb.

sbmellen

...and t-stat was replaced when the belt was changed @ 62K in '03.

I think I'm going to do the t-belt again this year. Probably next month.

Thanks, guys.

RedBlackYellow

what's the figure on that receipt?

sbmellen

Labor @ stealership: $630. Parts from PureMS: ??? Lost the parts receipt or can't find it.