I have an '02 Durango SXT 4.7 Litre w' 133K klicks. A few weeks ago the A/C compressor seized, so I had to replace the unit. The car would never warm up past the 'cold' indicator on the temp guage, and I replaced the thermostat so it heats up perfectly now.
The problems are these -
Since the repairs, at 4,000 RPM, the car 'chugs' violently like it's misfiring or starved for fuel...but ONLY at 4K (??)
since before the repairs, and still now, I get 5 KM per litre. It's supposed to be, what? double this??
I came to the conclusion that maybe because I was running very rich to compensate for the cold temps that the plugs are messed, and intend on changing them, but would plugs only misfire at high RPM's?
any other thoughts or ideas?