Hi all,

I recently traded my Passat for a G35.
Everything seems good apart from a few things, the main one being that I am unsure if the head gasket is gone (or something else).

So I bought the car from the seller claiming it had a BHG but when I brought it home I found a hose going through the firewall (heater matrix?) which was busted and throwing all the coolant out. I've since replaced the hose and refilled the system, ran it up to temp and the needle goes between H and C and doesn't move at all. I've noticed some little bubbles appearing in the expansion tank and the top radiator hose seems to alternate between being soft and then hard (but still squeezable).

What should I be looking for if the head gasket is gone? I'd rather not simply drive it till she over heats...... Are those bubbles normal after refilling the system?I had opened the bleed valve and let the air out - not sure if it's all though.


The other issues with it are somewhat minor:
The passenger side window doesn't operate, most likely the motor?
I think there's a small oil leak (few drops on drive) most likely to be from where?
Rear center brake light behind the rear window is out.
Brake light (or so I think) is very pink and looks damaged on the wing.

Apart from those minor things, she doesn't look bad for 150k miles.

 

Check and see what color the oil is. If it looks milky than it's coolant mixing with oil which are symptoms of a bad head gasket. Also you can rent one of those combustion leak testers from autozone to confirm if you have a bad head gasket as well. Also, one of the main symptoms is smoke coming from your exhaust that has a sweet smell to it, which is coolant burning in the cylinders. P.s I don't advise you stick your face in the exhaust pipe to smell it while the car is running.

 

The Oil is very clean.
I think the next thing I'll do is the leak down or a compression test.
There is no smoke whatsoever from the exhaust and smells completely normal.

Thanks for the response, really hoping I get lucky here......

 

Got air in the system or bad thermostat

 

Buy this and burp the system

 

Okay so after a 10 mile trip she overheated with no indication. The temp gauge was right between hot and cold, not shuddering, hesitation or apparent sign of overheating. Whilst slowing for a turn as the revs dropped it just stalled completely. Wouldn't turn over. About an hour later it turned over but wouldn't start.

Anyone can enlighten me why my temp gauge didn't move and why she won't start back now even though it cranks strong. Any sort of overheat protection here? Or have I just lost compression......

Any help is appreciated

 

Air in the system around the temp sensor could do that.

 

So I've tested the compression and had values as low as 10psi. Not sure what factory numbers are but I know this is definitely too low anyway.

Unless I find a well priced engine soon I will go ahead and changed the head gasket, straighten and plane the heads if needed and so on. Before I can see how far the damage is gone I need to remove the heads.

Since searching I haven't found a definitive write up for head gasket replacement. It all appears straight forward but my main concern is with the timing chain, setting the timing correct and working with those moving exhaust cam sprockets. If anyone can provide advice or any tips I should know before starting that would be great.

Thanks again
Brad