P0302 and P0420 Codes: Need Help, At Wits End
#1
P0302 and P0420 Codes: Need Help, At Wits End
Hey all,
I need some help here, or at the very least a direction to start moving in. For the last I'd say 3-5 months, I've had the P0420: Catalyst System Below Efficiency Threshold - Bank One code coming up, as will as the MIL on the dash. I should say that I have noticed no ill effects that would be indicative of a faulty cat. There is no stumbling, stalling, rough idle, power loss, etc.etc.etc. The car runs beautifully.
However, New York requires a annual inspection, and I'm about 3 weeks overdue for it. I have tried everything I know to get this fixed (repairs and fixes listed below). This past week I had it looked at in the h̶a̶c̶k̶ ̶s̶h̶o̶p̶ auto shop and not only were they unable to diagnose it, they even managed to produce a new code, a P0302 Cylinder 2 Misfire code. So I need some direction as to what my next step(s) should be considering that I now have a P0302 and P0420 code.
I should also note that the car was struck by lightening several years ago which caused a host of problems that was ultimately attributed to being a fragged ECM. Replacing the ECM cleared up all of the problems.
List of fixes:
-Replaced leaky flex pipe on exhaust line - no effect.
-Replaced downstream O2 sensor on Bank 1 - no effect.
-Ran injector cleaner through tank several times - no noticeable effect.
-Ran Cataclean through tank twice - Cleared P0420 code for about a day.
Thanks in advance for any advice or help.
I need some help here, or at the very least a direction to start moving in. For the last I'd say 3-5 months, I've had the P0420: Catalyst System Below Efficiency Threshold - Bank One code coming up, as will as the MIL on the dash. I should say that I have noticed no ill effects that would be indicative of a faulty cat. There is no stumbling, stalling, rough idle, power loss, etc.etc.etc. The car runs beautifully.
However, New York requires a annual inspection, and I'm about 3 weeks overdue for it. I have tried everything I know to get this fixed (repairs and fixes listed below). This past week I had it looked at in the h̶a̶c̶k̶ ̶s̶h̶o̶p̶ auto shop and not only were they unable to diagnose it, they even managed to produce a new code, a P0302 Cylinder 2 Misfire code. So I need some direction as to what my next step(s) should be considering that I now have a P0302 and P0420 code.
I should also note that the car was struck by lightening several years ago which caused a host of problems that was ultimately attributed to being a fragged ECM. Replacing the ECM cleared up all of the problems.
List of fixes:
-Replaced leaky flex pipe on exhaust line - no effect.
-Replaced downstream O2 sensor on Bank 1 - no effect.
-Ran injector cleaner through tank several times - no noticeable effect.
-Ran Cataclean through tank twice - Cleared P0420 code for about a day.
Thanks in advance for any advice or help.
#2
#3