slightly running hot - intermittent
 

I changed the TB/water pump/thermo on my car around xmas time. Since then, I've driven about 3,000 miles and the temp gauge will randomly go up to 1:00 position and then slowly come back down.

It never goes past that point and I can't find a real pattern. It's done it at anywhere between 20 degrees and 65 degrees (outside temp).

Admittedly, I haven't done any troubleshooting but should probably get this sorted out before summer is here and I'm in traffic with the A/C running. I immediately replaced the fan clutch when this first happened because it didn't have any resistance, but that didn't make a difference.

I can't believe that I have an airlock with all the miles I've driven but maybe I should re-bleed the system? I also doubt that the thermostat would randomly act "defective" but I'm open for suggestions.

I have verified that the electric fan is coming on and I'm sure that is what causes the temp to rapidly come back down when it hits the high point. I can watch the needle go from 1:00 to 11:00 in about 30 seconds.

A guy on the A4 forum changed his TB and has had the exact same problem but hasn't figured it out yet. I verfied that we have different thermostats.

Any ideas?

Bob

Is your electric fan works? Mine died a few months ago.
 

I guess I have to replace it. Does anyone have a procedure for a fan replacement?

menopause?

yes, the TB procedure will show you how to remove the electric fan

Also worth checking the clutch on the mechanical fan.
 

Stick a pencil in it.

Sorry. I was being a smart*ss.

I did that on the old one and it stopped easily. The new one would cut your finger off...
 

but no difference with this issue.

I figured you must have known that :)

coolant temp sensor?

you know, that's the first thing I would have replaced if I hadn't just done the TB job
 

seems odd that this started just after I had my hands on it. Never touched the temp sensor though but maybe it's a weird cooincidence.