My Mercury Cougar is missing. We replaced all spark plugs and coils on sat and it is missing a little still. I also added fuel injector on Thurs. Anything else I should check or replace? The car has 160,000 miles, V8 and I get 26 miles per gallon. Thank you
Our team suggests to try having a compression test run on all cylinders. If the compression is below 125 psi that is the likely cause of the “misfire”. This type of repair is costly, may be a leaky valve. If the compression is good, start looking for an air leak at the intake manifold. This can be done with an explosive spray cleaner (carb cleaner, not brake cleaner). Care should be taken NOT to spray coils or exhaust as a fire may erupt.
Hope this helps and good luck!
〉 Answered on Mar 7th, 2012 by Judy Curry, Co-Founder and Vice President of Marketing at Currys Auto Service
Has the fuel filter been checked for replacement?
〉 Answered on Oct 25th, 2013 by Colleen McGee, Driving Instructor at Americas Driving School
Emily, Provided that you also replaced the spark plug wires in conjunction of your spark plugs and coil packs I would check your idle air control valve.
〉 Answered on Oct 25th, 2013 by Amanda J. Pierce, MBA "AJ", Certified Mechanic, Project Coordinator; Primavera Scheduler at VIGOR Alaska Industrial Shipyard & BizzM3ch Solutions
Change the spark plug wires too.
〉 Answered on Oct 25th, 2013 by Barb Petrey, President - DBK Enterprises Inc at Jiffy Lube
Have a qualified techician check for relative compression before you put any more parts on the car. If the base mechanics are not working correctly, changing more parts will not fix this. Incorrect sensor readings wil also cause poor drivability/misfire concerns. Lazy 02 sensors, MAF, Idle control, vacuum leaks, etc.
You will be much better off having this properly diagnosed than continuing to replace parts.
〉 Answered on Oct 25th, 2013 by Helaine Kurot, Owner/Technician at 360 Automotive