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1064 Views 7 Replies 4 Participants Last post by  phantom GLI
My '99 GLS 1.8T seems to have a slow leak.

Apparently the leak only occurs when the engine is running, it is a slow seep.

The coolant is dripping onto the right side of the Transmission differentiial housing I have tried to locate the source all day yesterday but can't see much since the exhaust manifold is blocking the view on top and the subframe is blocking the view from underneath.

Does anyone know of any coolant lines that are routed on the right side of the engine. Around the turbo is dry and the leaking coolant does not seem to be hot when it drips. While I had the car jacked up I changed the thermostat.

I hoping that maybe someone that remove the turbo to upgrade or do some repairs could tell me what could be the source if any or has anyone else experienced this.
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Anyone :roll: no suggestion is too crazy, I am trying to figure it out now before it gets serious. I will monitor it for the next week to determine how serous it is.
Could iot be rolling forward fromthe head? I had the primary coolant T on the back of the head lose its seal a while ago, I had to pull it off and replace the o-rings on it. Total PITA, but it fixed it.
I looked at that but I am not convinced that it is the source. Where does the coolant return line for the turbo go?
Check the coolant temperature sensor to see if the seal is seeping. You should be able to see it from above when looking down between the back end of the valve cover and the firewall. When I replaced mine the new seal I got from the dealership was the wrong size and it leaked slowly and caused a drip in the location you are describing.

Good luck.
Jaero when I say the differential housing I mean the right side of the transmission where the axle attaches this is where the drops are coming from, Like I said before the coolant is not hot by the time it gets there. Was this the same location that you leak was showing up? the is quite weird because even if the rear of the car lower than the fron the coolant still appears at that point. I looked at the coolant tempreture sensor housing, but I figured that if that was leaking the cooland would fall on to the bellhousing. Lemme know if your symtoms are different from mine.
phantom GLI: Jaero is exactly right. In my case it was the black plastic "T" that the temperature sensor sits in, not the seal itself. I had done some engine work and apparently put some pressure on it and it cracked with a hairline fracture down the back of the T. It weeps and runs down onto the bell housing (but you can't see it on the housing), then down onto the diff housing exactly where you're talking about. Very hard to track, but it's coming from there.
Thanks guy All three of you are pointing to the same area I will zero on the problem and post my findings.

Remeber Don't hand me no jive about driving a :b5:
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