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Thermostat Open and Check Engine Light Is on – What Are Potential Issues?

(1999 BMW 328i)
in Santa Monica, CA on September 06, 2010
My 99 328i has a check engine light on. I scanned the Car with a scanner that can scan for BMW propriety codes and it says the my thermostat is open. What are the potential issues if I keep driving the car with the check engine light?

Thanks,
Displaying 2 answers & 2 comments
Popular Answer
on September 06, 2010
Your engine will not reach operating temperature, causing it to be produce more emissions and be less fuel efficient. You have poor heater performance as well.
on September 10, 2010
Thanks for your response! Based on your feedback, I had the thermostat replaced and all is working well.

Cheers :)
of Daniel's Automotive on September 10, 2010
HOOK UP A SCANNER AND WATCH OPERATING TEMP
IF THE ENGINE IS COLD ALL THE TIME, THEN THE CAR WILL RUN RICH, USING
EXTRA FUEL PLUS DAMAGING RICH CONDITION.IN AN EXTREME CASE , THERE IS AN INTERNAL FIGHT BETWEEN COLD AND HOT PISTONS BECAUSE OF THE VARIANCE IN COOLANT TEMP.ALSO OBSERVE LONG TERM FUEL TRIM.REPORT BACK WITH FINDINGS.
on September 10, 2010
Thanks Gentlemen for your responses! Based on Bretb's feedback, I had the thermostat replaced and all is working well.

Cheers :)
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