O2 sensors??????????

[ssmoke14]

My 04 Marauder just recently hit 90k miles. My check engine light came on. About a day or 2 later, it started idling rough. Advanced told me it was the O2 sensors by the cats the first time. I went to buy the sensors and got them to check it again and this lady told me it doesn't really mean its the O2 sensors and that both probably wouldn't go bad.

[RF Overlord]

Post the actual code(s) so we know what we're dealing with.

...and "this lady" is probably right...O2 sensors don't usually go bad in both banks at the same time. Your symptoms sound like a vacuum leak (unmetered air).

[fastblackmerc]

Post the actual code(s) so we know what we're dealing with.

...and "this lady" is probably right...O2 sensors don't usually go bad in both banks at the same time. Your symptoms sound like a vacuum leak (unmetered air).

Yep... need the actual codes to help you out.

[ssmoke14]

Ill try to get the codes. Stuck at work now. Has anyone else experienced this problem? I'm not sure if she ran the test correctly.

[ctrlraven]

By chance do you have a hand held flash tuner? If so you can pull the codes yourself with it.

They could go bad at different times or the same time, anything is possible. Have you recently done work or had work done to the car?

[ssmoke14]

I just had an oil change about a month ago.

[ssmoke14]

And I don't have a flash tuner.

[ctrlraven]

Yeah once we know the codes we can help you more.

[ssmoke14]

Ok I got somewhat of a code. I had to call and ask if she remembered. Cat efficiency threshold bank 1 and 2. Lol I hope this helps so I can get help.

[ssmoke14]

P0420 I think from researching myself?

[RF Overlord]

The rear O2s only monitor cat efficiency...they have nothing to do with the engine's operation, so they wouldn't be the cause of your rough idle. Something else is causing both conditions. Although they could have both gone bad at the same time, that's too coincidental with your other symptom.

[ssmoke14]

Guess I'll be headed to the dealership. :censor:

[ssmoke14]

Any more suggestions?

[ssmoke14]

I do remember the lady saying something about my car or the readings were lean.

[MM2004]

I do remember the lady saying something about my car or the readings were lean.

Go back and have them hook-up a scanner to it again.

Autozone will give printouts of what the results are. (Free)

Accurate codes are essential in diagnosing what the issue(s) is/are.

Hold off on going to a Dealer until you post up with the code(s) and may very well get an answer here and save you a helluva lot of $$.

;)

Mike.

[RF Overlord]

I do remember the lady saying something about my car or the readings were lean.That points to my original answer ^^^ ...unmetered air. Look for a loose clamp on the intake tract, or a vacuum hose that's cracked or dislodged. The PCV valve hose has been known to do this...

[ssmoke14]

Will do. Thanks everyone for the help. I'm about to worry myself to death. Love my car!

[ssmoke14]

Ok, the rubber hose connector that goes directly into the top of the intake is split. Does anyone know what its called and if I can only get it at the dealer? It has a small hose on each side of it.

[ssmoke14]

This is the best pic I could get. http:// http://www.google.com/m/search?site=images&client=ms-android-att-us&hl=en&gl=us&source=mog&aq=f&oq=&aqi=-k0d0t0&fkt=1172&fsdt=32034&cqt=&rst=&htf=&his=&maction=&q=2004+marauder+engine+photo#i =1

[ssmoke14]

http://www.google.com/m/search?site=images&client=ms-android-att-us&hl=en&gl=us&source=mog&aq=f&oq=&aqi=-k0d0t0&fkt=1172&fsdt=32034&cqt=&rst=&htf=&his=&maction=&q=2004+marauder+engine+photo#i =1

[fastblackmerc]

No picture......

Any Ford dealer should be able to find the part for you.

I sure it's a "dealer only" item.

[ssmoke14]

Pic of the part I need.

[ssmoke14]

http://www.mercurymarauder.net/gallery/showphoto.php/photo/20332/ppuser/4342

[RF Overlord]

Looked at your pic... :eek:

yup, that would definitely cause a bad idle...

You might be able to find a "close enough" rubber elbow in the HELP section of AutoZone, Advance Auto, or whatever you have near you. You could also try RTV as a temporary band-aid until you can get something more permanent.

Maybe someone with a Trilogy would have that piece left over and be willing to part with it, otherwise it probably is dealer-only.

BTW, that is part of the PCV system. The PCV valve is at the other end of that rigid tube in the passenger-side cam cover.

[MOTOWN]

Looks like this mystery has been solved! hope you can locate a replacement part

[ssmoke14]

Ok. I looked for a replacement but the part is graduated so I didn't have any luck. You guys have been so helpful. Just wanted to say thanks. I just put tape on it for now.

[ssmoke14]

Hey fellas, I got the part ordered. In case someone else has this problem this the part number. 3W3Z-6758-BB Tube Assembly $20-$30. Thanks again for all the help.

[ctrlraven]

Glad you got it solved!