Problem occurs when RPM is higher than 2750
Problem started up immediately after replacing the AC compressor, harmonic balancer and serpentine belt.
I had replaced the spark plugs this past March along with air intake filter, and MAF in order to pass the required smog check.
I have now replaced the spark plug wires and the ignition coils.
There is no physical manifestation of the misfire. Engine runs smooth, no apparent lost of power.
Check engine light appears and then disappears. Reading the error codes indicates:
Random misfires all cylinders
Misfire cylinder 1
Misfire cylinder 4
1999 Mazda 626 ES 2.5 litre V6
Any suggestions where to look next?
Problem started up immediately after replacing the AC compressor, harmonic balancer and serpentine belt.
I had replaced the spark plugs this past March along with air intake filter, and MAF in order to pass the required smog check.
I have now replaced the spark plug wires and the ignition coils.
There is no physical manifestation of the misfire. Engine runs smooth, no apparent lost of power.
Check engine light appears and then disappears. Reading the error codes indicates:
Random misfires all cylinders
Misfire cylinder 1
Misfire cylinder 4
1999 Mazda 626 ES 2.5 litre V6
Any suggestions where to look next?
Images (Click to enlarge)
Sep 27, 2026 at 8:58 AM