Originally Posted by BMWnoob
methyl hydrate.. google tells me this is antifreeze... i just pour some into the gas tank.. is this going to cause harm? ...
Gasline antifreeze, not just "antifreeze". Burns cleaner and hotter than gas, as it's alcohol IIRC. I'd probably try and fix what's broken first, methyl hydrate as a last resort.
Spark plugs, adjust your valves, O2 sensor to start with, don't forget a new air filter if it hasn't been done.
Just a though, if it's rich at idle but not off idle, could it be the TPS idle switch not connecting properly (ie/ car isn't going into the idle loop, dumping too much gas at idle?) With the car off, open your hood and move the throttle butterfly from closed to open, and then let it close again. Listen closely to see if you can hear a quiet click. If no click, it's not hitting the idle microswitch.