2008 Mercury Mariner 2.3L 4 cyl (Mazda Engine) from North America
Summary:
Long lasting engine, but 2.3L is underpowered
Faults:
I replaced the Idle Air Control (IAC) valve shortly after purchase to take the idle back down about 300 rpm to a normal 650-700 rpm.
Added a bigger transmission cooler. Drained and filled with 7 qts of transmission fluid.
I did the suspension and brakes just because I always do that with cars I get.
I replaced the throttle body, because it was sticking with junk yard throttle body and worked like a charm. This year does NOT have the ELECTRONIC throttle motor like the 2009 and newer which had known electronic issues.
I fixed the ignition play when turning the key with a plastic piece wedged to take up space in the housing, which was known to be slightly too big causing the key to turn without starting the car.
The steering sensor had a factory recall, but I never had them "reprogram" the computer, because it would then actually void the warranty if sensor went bad.
The transmission mount causes vibrations to enter the cabin via the steering wheel. The balance is off and mechanic says it is normal for this vehicle. You can feel the most vibration on the left most cylinder. I replaced all the mounts and had the vibration disappear for a few days after doing the transmission mount, but it was short term fix only.
I had a spark plug get loose due to the vibration and crack the coil pack and fly somewhere on the road. Engine vibration over time probably to blame. So, new coil pack and spark plug fixed it.
Exhaust rusted near intermediate muffler due to Northeast Ohio use of road salt.
I had the thermostat housing replaced by mechanic, because it was easier to do with a lift than in my driveway.
I replaced the gasket on the intake manifold.
I replaced the rear control arms to get the alignment to stay in the green.
I replaced the lock actuator in the rear because it was sticking.
Replaced headlights with LED because I couldn't see while driving at night with the standard headlights.
The vehicle struggles to go fast on windy days, so I would say having a roof rack is just making it worse. I tried to remove it but the screws were super tight and could not be loosened.
I did fuel system cleaning at a mechanic with no change in MPG.
I did an air intake service with slightly improved idle afterwards.
General Comments:
It is an engine that will not allow easy merging because the vehicle is underpowered and it shakes despite a lot of effort on my part to figure out the issue. I would recommend this vehicle only for those that just drive around town or don't commute to work everyday with it. The engine is known to go 300k miles, which most modern cars cannot achieve even with more engine sensors.
Would you buy another car from this manufacturer? Yes
Review Date: 23rd February, 2024
13th May 2018, 14:09
Total amount of miles?