P0420 with P0102

[posthuman63t]

Hey guys...This is for my cousins Cougar (V6), my car is still F---ed up. Anyways, I looked up the codes, and also searched the new and old forums to see if I could find anyone who had similar problems to my cousin.

Most threads I have read have said it can be a false code, or they have experienced no drivability issues, just the code popping up (and a lot of suggesting of using mil elims). My cousins ride however, feels like there is a loss of power in low rpms. Primarily when he is just starting to move (low rpms) and even when he is cruising the back roads at 50mph and the engine rpms are low. However, through the rest of the rpm band, he has no issues (apparantly) and there is no idle issue.

As for the P0102, I havent found anything other than cleaning the MAF sensor.

Could the two codes be related, or is it just a coincidence? I do have a feeling his pre-cat may have failed, he did mention when the car idles for a while, he does smell strong exhaust fumes.

If anyone has some help you can throw our way, we'd appreciate it. Also if anyone wants to buy my car and fix the "wiring" issue or whatever it is thats wrong with it...make an offer!

 

[projectSHO89]

HIs driveability issues are related to the MAF fault, not the converter efficiency code.

Diagnose and repair the issues with the MAF first. It is unlikely that it is only in need of cleaning.

Steve

 

[posthuman63t]

Maf was clean, problem persists with it plugged in or not. I'm leaning towards a fuel issue as his car has had some good gas fumes present while/after running. Possible fuel filter, or pump issue?

 

[projectSHO89]

Fix the MAF problem (is there an echo in here?).

With no proper MAF signal, the computer resorts to default values which, while the engine will run, usually give a rich mixture.

Steve

 

[posthuman63t]

the maf problem is what we are looking at. With maf unplugged the symptoms are the same with it plugged in. Are you saying that's cuz the maf crapper out, or could there be an underlying issue causing the problem.

 

[SVTCANUK]

If the symptoms are the same with or without the MAF plugged in then there is a good chance it's shot or the wiring is bad. After cleaning the MAF did you reset the computer by disconnecting the battery negative cable for a few minutes? The computer will want to see 2 consecutive drive cycles without a code before it will turn off the CEL and return to non limp mode by resetting it you can get the car out of limp mode quicker. This will also tell you if the problem is persisting because the CEL will come on again if the problem is still there.
For the P0420 just run some fuel injector cleaner through a few tanks of gas, this will help to clean the pre-cats a bit and possibly eliminate the code. As always with codes reset the computer to see if they come back.