Intermittent Coolant Leak

[d1owner]

I have a 97 D1 with 200K+ miles. Recently I developed an intermittent coolant leak. For the past 60K miles, the car has been dogged with coolant related issues. Just about all parts of the coolant system have been replaced/repaired.

I took it to the dealer for evaluation figuring that I had so much equity in them for their prior work that perhaps this may have been covered under warranty for one of the other items. Neverthelss, after a pressure test, they indicated I needed a new head gasket. Given that my first head gasket failed around 105K miles, I figured it was probably time again.

After the repair, I have noticed some intermittent coolant puddles below the vehicle. It is difficult to say when these appear. Most of the time, it is dry below the vehicle. My only suspicion is a loose hose connector, but everything seems fine. The puddles appear somewhere between the rear of the engine and the firewall slightly towards the passenger side of the car. Kind of where the connections are made to the heater core. I have felt around the hoses near the heater core and do not detect any wetness.

My best guess as to when the leak occurs is when the temperature outside drops significantly overnight. Could this still be an issue with the head gasket or is it something else.

 

[dhuddleson]

One possibility is the intake manifold gasket. While they use a special coated valley gasket as compared to the old plain "tin" ones, and you do NOT have to apply any sealant around the coolant passages, sometimes they are not torqued down "enough". The areas that should be checked are the rear of each head. Check the last couple of bolts from intake to heads, and see if a little extra "snug" might just stop the minor leaks. It is difficult to look into those areas to identify if they are the culprits...

Check hoses around as well. Also remember that coolant may leak from front area and flow to back of engine, then down each side to drip on catalysts or directly to ground...

Good luck, and hope it is as simple as something a little loose!

 

[garrett]

like David said the intake is a good guess. many times you will not see the leak as it burns on the cats as it comes off the back of the motor and bell housing. have a look on the cats and exhaust to see evidence of a white residue from the coolant. this will be the tell tail.

 

[d1owner]

Wouldn't I also see residue on the exhaust/cats if it was dripping from the heater core in/out lines? The funny thing is that I believe I have had the intake manifold gasket replaced not too long ago. Perhaps it does need to be tightened down after the head gasket job was recently performed.

Also, I do not smell any signs of coolant while driving. When my prior Intake Manifold Gasket (IMG) failed and I saw coolant on the valve cover gasket area, I was clearly able to smell the characteristic "sweet" smell of cooking coolant. Also, it does appear intermittent. I would figure if it was the IMG, it would always leave a puddle, especially when doing short drives where there is not enough time for cooleant to leak on the exhaust/cat and burn off.???

Also, I have not noticed any significant drop in coolant thus far (crossing my fingers)