Daughter's '98 C70 2.3L turbo recently showed codes for misfires in all 5 cylinders and P0172 (Bank 1 rich) Can't remember the rest, but I did replace the MAF which seemed to work. No more rough idling...car ran great. Cleared codes. This lasted about 2 weeks, then back to rough idle. Codes read P0302 (cylinder 2 misfire) & P0410 (Secondary Air Injection System). All spark plugs seemed in good condition, though the gaps were not checked. Compression good.
Had her clean the old MAF with MAF sensor cleaner and reinstall, sent the Delphi AF10311 MAF back for refund. Car seemed to run a little better, but for less than 1 day. Back to the rough idle. Had her clear codes to see what would happen. Got:
P0172, P0302 & P0410. Freeze frame info only on P0302, and is as follows:
- Engine speed - 840 RPM
Calc Load - 1.6%
Coolant - 210 F
STFTRM1 - -.8%
LTFTRM1 - -6.3%
Veh Speed - 6 MPH
Fuel System 1 Loop - Closed
Fuel System 2 Loop - N/A
- Check cylinder 2 spark plug gap
Might it still be just a bad MAF, and the Delphi replacement was a dud?
Check wires, caps & rotors
Have replaced some vacuum line connectors/elbows that were obviously leaking, but thinking another leak may be the problem. Get a smoke test?
Possible air pump failure?
Any suggestions would be greatly appreciated!