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steved0x · 07-17-2014, 12:16 PM

I had those codes intermittently off and one, along with a code that the heater on one of my post cat O2 sensors was failed. I also would get cat inefficiency codes, I got them for both sides.

I cleaned my MAF and put a new air filter. 1128/1130 came back.

Then over Christmas I replaced:
The one post cat O2 sensor
Plugs, tubes, and O-rings
new fuel filter

And the codes are gone. (I should mention that my gas/oil/coolant caps are all new as of a year or two ago)

I am not sure what happened, or which of these things resolved the 1128/1130 but they are gone and have never come back. A fair amount of oil was seeping out of the Spark plug tube O-rings so maybe some air was getting in? I don't know (and it sounds like you did the plugs/tubes) but that was my guess for mine. But 1128/1130 is also fuel related, maybe the fuel filter? Maybe it was the bad post cat O2 sensor throwing everything else off. Even though that sensor shouldn't be involved since it is only there to monitor the cat.

Good luck!

07-17-2014, 12:16 PM	#6
steved0x Registered User Join Date: Dec 2012 Location: FL Posts: 4,143	I had those codes intermittently off and one, along with a code that the heater on one of my post cat O2 sensors was failed. I also would get cat inefficiency codes, I got them for both sides. I cleaned my MAF and put a new air filter. 1128/1130 came back. Then over Christmas I replaced: The one post cat O2 sensor Plugs, tubes, and O-rings new fuel filter And the codes are gone. (I should mention that my gas/oil/coolant caps are all new as of a year or two ago) I am not sure what happened, or which of these things resolved the 1128/1130 but they are gone and have never come back. A fair amount of oil was seeping out of the Spark plug tube O-rings so maybe some air was getting in? I don't know (and it sounds like you did the plugs/tubes) but that was my guess for mine. But 1128/1130 is also fuel related, maybe the fuel filter? Maybe it was the bad post cat O2 sensor throwing everything else off. Even though that sensor shouldn't be involved since it is only there to monitor the cat. Good luck!