2003 Audi A4 1.8T, 70,000 miles.

I've posted here already about the new turbo put on about a month ago. Immediately upon getting vehicle back I noticed a rather small coolant leak. Leaves about an 8 inch diameter puddle when parked after driving. But the reservoir doesn't drain quickly (I've had to top it off once in the past 3 weeks).

Today I finally got under it, took off the plastic undercarriage cover, and I think I tracked down the source. I'm 98% sure it's coming from one of 2 hex bolts on the side of the turbo (photos attached). First of all, does anyone know if that's a likely place for such a leak to originate? Secondly, can I safely crank down on this hex bolt to try to pinch it off? Or is it more likely I need to replace the part altogether?

 

I would look to the coolant flange, the thermostat, and the waterpump before looking where you are looking. Also, I think the turbo is oil cooled, so no coolant goes there.

 

I lay under there immediately after driving, and could see coolant seeping out from around that hex, watched it run down the support beam and drip, drip, drip. If it's not from there, it's from somewhere in the immediate vicinity (like, within 2 inch radius).

 

Its both......

 

When replacing the turbo you need to be thorough about tightening all fittings before installing. even the ones that already come with the new turbo. Sometimes they are left loose. So i would make attempts to tighten all the line and fittings