I've had my Toronado for several weeks now. The seller stated that the engine was bad, but didn't elaborate - was looking to dump it. The price was right so I took a chance. Car seems to have about 50,000 miles verified by tire warranty card for the tires currently on the car that were installed in 1980. Starter was shot, radiator was shot, previous owner had installed chrome valve covers with NO crankcase ventilation or PCV. I fixed all these problems and the car runs great. Compression is very even at about 165 psi per cylinder. Here is the problem: When you let off the gas from cruising and the engine goes into a state of high vacuum, it sucks coolant into the combustion chamber(s) and makes a huge cloud of coolant scented steam from the exhaust. The cooling system does not become pressurized when driving. No coolant is escaping from the overflow tank. I removed the intake manifold in hopes that the gasket was leaking coolant between one of the coolant passages and an adjacent intake runner. I found no evidence of this. As an Oldsmobile big block newb, I'm wondering if it could be possible that the intake could be cracked between coolant passage and intake runner, or if I could be looking at a cracked head (but not cracked in the combustion chamber because this would likely cause pressure in cooling system)? I'm very confused by this problem. Have never run into it before. Any suggestions are very welcome.

Steve Hart

 

My fresh Pontiac was using coolant; I used head gasket repair and it actually solved the problem. Might be worth a try. Pretty cheap. If it doesnt solve the problem pull the heads and check everything out. Is it both tailpipes or just one?

 

Since you checked compression, I assume you didn't find a plug or plugs that were abnormally clean?

 

Coolant Dye & Ultra Violet Light test ? kit

 

If you do try that junk make sure and totally flush your cooling system immediately afterwards. I have seen what it does to coolant passages

 

And heater cores. I will not use that stuff in a vehicle I care about.

 

The number 1 plug was cleaner than the rest, and the intake port is adjacent to the left front water port on the manifold, but I found no evidence of coolant leakage when I removed the intake. Maybe something will show up once I get the parts cleaned up.