burning rich
- Thread starter roadrunrx
- Start date
If there is fuel in the oil it means there is either blowby, which means the piston rings are worn, or the cylinder wall is scored - OR, it means your thermostat and/or engine temperature sensor is bad. If your thermostat is bad and always open, the car will never fully warm up, and the ECU thinks the engine is cold. The ECU uses a 'warm-up' mode, which dumps more gas into the motor for cold starts on cold mornings.
The same thing would happen if the temperature sensor is bad...ecu wouldn't know the engine really is warmed up.
I'd say change the thermostat and the temperature sensor (note: Not the "VDO" or temp GAUGE sensor - the ECU's temperature sensor...they are two different items). It'll cost you all of $50 including antifreeze and about 45 minutes if you do it yourself.
The same thing would happen if the temperature sensor is bad...ecu wouldn't know the engine really is warmed up.
I'd say change the thermostat and the temperature sensor (note: Not the "VDO" or temp GAUGE sensor - the ECU's temperature sensor...they are two different items). It'll cost you all of $50 including antifreeze and about 45 minutes if you do it yourself.
ya'know what, i think you're right because the same thing happened to me years ago in an acura integra. it was my first instinct when i bought the car with my son but the previous owner said it was the mass air flow sensor. just goes to show you that following first instincts is worth alot. by the way we bought the car for $250.00 and that's the only thing wrong with it. thanks for your input and the valuable lesson you've taught me.
Cylinder Leakage Test is were u apply shop air to the cylinder area (all plugs removed and engine warm) while the engine is in Top Dead Center (TDC) but in the compression stroke and you don't crank the engine over with this test. You then get a % of leakage for the cylinder and check the specs to see if its in range.
thanks epj3, i've got a spare thermostat but i will test the temp sensor just to be sure. it's interesting to note that eventhough the different auto manufacturers have different names for their fuel injection systems the basic priciples are the same. when he told me the problem was the mass air flow sensor i thought to myself "if that were the problem then it would'nt start" based on my previous experience. anyway thanks again for the helpful info. but don't go away so fast, i've got another question. my other 533i has a loud valve tap even after adjustment. i guess the cam is worn. would it be a good idea to to adjust the valves down to .090 or to some degree beyond the specs to eliminate the valve tap and hopefully improve engine performance. really, the car idles fine and accelerates well as is but it's noisey. your thought please.
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You usually replace a thermometer when you flush your coolant so if it is gunked it won't happen again.