I'm loosing about a quart of coolant every 2 or 3 tanks of gas. I don't see any leaks and I don't see any sign of it coming out the tailpipes such as a head gasket leaking. Oil is normal looking too.

My question is; where are the typical and non-typical coolant leak areas of a TPI engine. Do they leak at the back of the intake like a Vortec motor? or do the soft plugs leak? Or if it is a head gasket could it be that it is being burnt up through the catalytic convertor enough so that it doesn't blow vapors out the exhaust?

It has done this since I've owned it and it has new radiator hoses and thermostat and housing.



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I seem to be in the same boat in terms of symptoms. Any suggestions would be very welcome.

Update on my problem: Put a pressure tester on the system and found a very slow leak at the upper radiator hose / thermostat housing connection, but the main problem is a leak at the plastic end cap on the radiator.

Mine leaks there too. Right at the upper hose/thermostat AND at the upper hose/radiator. It sucks. Also, the water pump will weep water when it's going out. And if you can't spot ANY coolant anywhere, at all, lift up the carpet in the passenger footwell, and I bet the padding under it is wet. My carpet was NEVER wet, and my car never smelled like coolant. But when I ripped out the carpet that padding was SOPPING.

I put a pressure testor on mine too, when warmed up it held 20PSI for about 10 minutes then sunk down to 15PSI after a half an hour. Next day when cold it wouldn't hold 20 PSI for more than 5 seconds.

I'm leaking at the coolant bypass into the front of the intake and at the drain petcock...so far.

I'm going to replace all the small hoses when I pull the intake here soon.

TheScaryOne is right on. It sounds like a bad heater core. I just went through that. It can leak for a long time without being obvious.

I have the carpet out now(to replace), I'll have to check my heater core now with the pressure testor. But I think mine are the two I mentioned earlier....I hope....

Replacing that was the previous weekend's project. Mine didn't wreck the carpet, but it fogged the windshield so bad that I had to wipe down the windshield every five minutes while getting it home. The car got parked that night for a heater core change.

dont go past 15 mabey 16psi. seals/hoses dont like 20psi.