Two codes, PO171 and PO174
I have searched and couldn't find any info on fuel filters. Does this car not have one? It's my G/F's car. I have an intake on it (generic gauze type filter) it also has a header, high flow no cat midpipe and a low restriction muffler. I also have an O2 simulator on it which is working fine. I have had all this stuff on since January with no problems other than an O2 sensor going bad. I have rechecked everything and nothing is loose or broken under the hood. It has 50,800 miles on it.
I took the air filter off the other day and cleaned/reoiled it and put it back on. I have already checked the maf to make sure it has no oil on it, it's clean. I had the codes read this morining and reset and the CEL came back on this afternoon, like 20 miles. I just can't see both primary O2 sensors going bad at the same time. I am thinking a clogged/dirty fuel filter or injectors. Any thoughts? Any help? Thanks guys.