if your coolant level is low, and you can't find any external leaks then it only got one other place to go :(

Normally that sealer **** they sell won't help if you have a bad coolant seal, but there is one on the market, it looks like a bottle of black liquid and it has theese pellets at the bottom that look like mouse poop. that stuff will work for a while. I put a bottle in my FD when one seal started going bad. I got 2 more years out of the motor, beating the piss out of it anywhere from 12-18 psi of boost. AND THEN SHE DIED :(

wouldn't the check engine light come on, if the O2 sensor was bad?

And if your Injectors were leaking wouldn't you be running lean instead of Rich, since you're losing fuel.

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