Need help guys - throwing alot of codes
I did a head gasket job for driver side bank (burning coolant, all good now)
And even before this job it was throwing the following code:
P0155 - 02 Sensor Heater Circuit Malfunction (I'm tuned for no cats I think and running no cats)
And now:
P0155 - 02 Sensor Heater Circuit Malfunction
P0300 - Random Misfire
P0305 - Cyl 5 Miss
P0306 - Cyl 6 Miss
P0307 - Cyl 7 Miss
CEL is flashing, and missing under 950~650RPM's codes are registered
So far I've done the following:
(x)Replace driver side bank spark plugs
(x)re-check all connections
(x)Put injector cleaner and 5L of 94 gas
(x)check oil level
---- start engine ----
Still misfiring
(x) replace Secondary Air Injection switch valve
(x) check PCV and EGR for clogs on valve covers and clean them
(x) Check PCV breather tubes for clogs
(x) Check vacuum lines
---- start engine ----
Still misfiring
Please help!
Last edited by benz_addict; Apr 12, 2011 at 08:08 PM.
I am going to swap the wires and coil packs around to see if the problem goes to the other side.
If that doesn't work then on further research found that pre cat, sensor 1 bank 2 needs to be replaced. P0155 comes on with misfires only for this side of the bank. Fingers crossed.
Last edited by benz_addict; Apr 13, 2011 at 02:12 AM.
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Cold start it'll be fine revving around 1k rpms as soon as it drops to idle it starts to misfire random, 5 and 7 cylinders. Freeze Frame data says 550RPM's for both and random and light flashes repeatedly.
I've replaced the O2, swapped wires and coil packs, plugs and checked for vacuum leaks. Coil packs work fine on the other side. I found a small hair line crack in one of the lines I'm going to replace it.
But as of yet it's still misfiring.

Last edited by benz_addict; Apr 13, 2011 at 05:34 PM.
I'm thinking I check timing again for proper alignment maybe it skipped a tooth during installation of the head.
Keeping an eye on this thread as I fight my own demons over here with misfire codes.
Right now its war with a shorted O2 sensor.
I give up








