upon startup, failsafe mode appears and check engin light also. Car runs well.
Use a Code Reader. If Check Engine light is on engine code is Written to computer and you can then find the problem. Go to AutoZone and get a free code test. Then they can tell you what part is needed. Thanks
Search Mercury Montego Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Mercury Montego Experts