I have a 2004 Taurus SE w/ a Vulcan engine( w 100k miles and health problems).
From all my research p0171 and p0174 are fairly common on the Duratec, but i cant find a lot of infos on Vulcans with this problem. My car was running like a real piece of crap last winter, turns out i drove it with lean codes for tooooo long. The first thing i did was change all four o2
sensors, with no luck. Next i changed the spark plugs and wires figuring that 100k was probably about time. No luck from that either! Next was the PCV
valve, still no luck. It really started misfiring, so i took in into the shop and they said i had fried my cats, so i replaced all 3 cats and cleaned out the exhaust. Good results it ran about 50% better than it did previously, (and sounded better too!) but still wasnt quite firing perfectly.
I took it into a muffler shop to check my exhaust out and make sure i hadnt screwed anything up and they did a diagnostic with a smoke machine and discovered i had a cracked intake manifold. I replaced that piece as well, reluctantly, but it really made a big difference and gave me another 45% increase in performance... that puts me at 95%!
so its running quite well now but i am still getting a CEL
and it is throwing codes P0171 AND P0174, which the guy suggested could be related to the MAF
sensor or the IAC
. I had pulled the MAF
previously and it looks fine, there is no gunk on it, i cleaned it with MAF
cleaner just to be sure but didnt notice a change. The IAC
looks fine too, no gunk, it moves freely.
I guess my initial question is, can i take my car somewhere to test the MAF
sensor?? I believe that previously a mechanic told me he had taken the MAF
"out of the loop" and it hadnt made a difference, but he told me some other wacky stuff too so im reluctant to rely on his word.
My next question would be, If the MAF
is truly fine, what could my next step be? Could driving on a lean condition have gunked up some other part that i havent yet cleaned or replaced?? Thanks for any suggestions, and for reading this lengthy post. Frustrating!