Trouble Codes P0171 & P0174 HELP!

OK this thing is driving me crazy, for about 3 months now I've been fighting these codes, from what I've read on line its a Lean Condition Bank 1 & Bank 2, now before you start pointing out the obvious, I have done this

1 Replaced the MAF sensor
2 Replaced all 4 O2 sensors
3 Replaced the Gas Filter
4 I cant find any vacuum leaks and the CAI is tight so its not leaking air, and this is the same CAI that has been on the car for the last 4 years with no problems.

Just for extra I don't know why, other then I'm sure the car needed them I have also replaced the

6 Spark Plugs
7 Plug Wires
8 Coil Pack

The only symptom the car has is that sometimes when you start the car it starts to Idle Ruff, it seems to me that its loading up, after you rev it a few times it clears out and runs fine, so that leads me to believe that its putting to much fuel into the mixture, and that would be a Rich condition not a Lean one, so it sounds to me like its a false Lean code that's telling the computer to rich'en it up.
At first the codes would only show up after like a week of driving, then a couple of days of driving, and now the day after I clear them.

So, what do I do now

Sounds like it could be a vac leak at the intake manifold. Spray some carb cleaner lightly around it when the engine is cool. keep a fire extinguisher handy lol.

OK I'll try that, Thanks Bob

Hey Bob I sort of half assed tried that and the engine didn't make any difference, the engine wasn't cold though, but what else could it be.

Bad Tune!

Not a bad tune, I've been using this one for some time now and I have tied others as well

Take the oil cap off and see if there`s vac there.

I wouldn't assume it's a false lean code, carbon build up can cause a rough cold start as carbon acts a s a sponge and absorbs the a/f creating a lean a/f for a minute or two at cold start up until carbon soaks up enough fuel and condition returns to normal, first thing I'd do is look at long term fuel trim on both banks, which if it is lean you'll have maxed out or close to it the postitve correction factor , not sure where it is but if you see a positive value at roughly 10% and above and it climbs higher as you drive, then you'll know the ecm sees a lean condition and is adding fuel to compensate, however once it reaches max adaptive strategy, boom ON comes the cel.......I'd smoke test the engine to see if any vac leaks exist, my diagnostic fee would of been cheaper then all those parts you bought

I think the issue is what I talked to you about when I gave you my extra MAF sensor. The sample tube is too large. The velocity will change so drastically that it causes improper reading.

Like I said before put a multimeter on the MAF senser and watch the voltage.

mjr46, thanks but the parts don't bother me, I wanted to do all that anyway as I have 96000 miles on her now, and I would have done all that even if i didn't have a code, I don't think it carbon either as I run good gas most of the time and I run good gas treatment on a regular basis, and I cant imagine having a carbon build up with the way I drive, the gas pedle's on the floor more then anything else.
Oh ya, who are you, I don't think I've met you yet.

Will, I gave up on that JLT junk heep ages ago, that was the biggest waist of money for V6 that you can get, I stuck with the Brute Force that I had been using, and this is a recent problem, all though I did find the tube that runs from the valve cover to the intake wasn't on tight, I fixed that and the code hasn't come back yet, but its only been a day so we'll see.

Bob, I used the carb cleaner and there dosnt seem to be any leaks at the manifold, but it could have been that tube

Ed you still got that JLT intake?

Yup

Chris you gonna put that "Junk" on your weedwacker?

Big Blue wrote:
Oh ya, who are you, I don't think I've met you yet.

nobody important, I change tires and do a few lof's AT WAL-MART, carry on and nevermind me

OK well thanks for the help anyway.

LOL, Ed, MJR knows his crap. Don't rule out anything that he has suggested. Generally, both of those codes indicate a vacuum leak as some have already suggested. The fact that you haven't found it yet maybe soley do to the lack of the correct equipment to use to find it. And smoking it would also be something to do as Mike has already said.

Years ago, the winstars had this same problem. It was oil getting into the intake and detsryoing the rubber upper intake plenum gaskets. Checking for TSB's would also be a big help to see if anything is listed.

If you take it to Mike, I can garrantee he'll find your problem. He is a diagnostic wizzard!!!

PRO50SC wrote:LOL, Ed, MJR knows his crap. Don't rule out anything that he has suggested. Generally, both of those codes indicate a vacuum leak as some have already suggested. The fact that you haven't found it yet maybe soley do to the lack of the correct equipment to use to find it. And smoking it would also be something to do as Mike has already said.

Years ago, the winstars had this same problem. It was oil getting into the intake and detsryoing the rubber upper intake plenum gaskets. Checking for TSB's would also be a big help to see if anything is listed.

If you take it to Mike, I can garrantee he'll find your problem. He is a diagnostic wizzard!!!

shhhhhhhh "B"!!!!! I hope to be promoted soon from the automotive cleaners/waxes section up to the Filters and oils section!!! then I'll get to bring stuff out to the guys in the shop area....whooo hooooo that's when things really start happenin' P.S Bernie...on the windstar thing.....seen that one alot.....the tsb also came with a reflash (we neverdid that part) and some required a new style valve cover for the rear bank cause they also had issues with the rear grommet for the pcv leaking, which ED here said he found a loose line?? if he has a scan tool he can go in and check pending codes to see if it has already set, pending ED is when it sets on the first drive cycle = sees prob and if it sees it a second time in a row on next drive cycle = Hard code/moves up to CEL on..........but seriously if you have access to a scan tool with Data pids, look at the LT fuel trim on both banks and see what it is, that'll be how you can verify the fix/ know a prob is still present

OK man thanks, I'll have to get the Innovate out and check it.