One problem related to check engine light on has been reported for the 2008 Mercury Mountaineer. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Mercury Mountaineer based on all problems reported for the 2008 Mountaineer.
**************************engine will shutoff without warning********************** it has happened with various levels of gas, various weather conditions, and both while stopped and moving. The "check fuel filler inlet" light will come on. Sometimes, the check engine light will remain on, but will clear within the next startup or two. Car has been at dealers at least 4 times for issue. Engine throttle body and crankshaft sensors have been replaced. In the beginning, the vehicle would do this once or twice, then run perfectly for months at a time. Each time it is "fixed" by dealer, who claims they cannot replicate the problem. Lately it will stall 4-6 times within a 30 minute period. Last month, I was able to read code 2107. Today, it stalled again 6 times, no check engine light remains, no code to be read. When car is running normally, it sometimes hiccups and seems to run rough.