Went out to about a 50 degree fallmorning preparing to go towork, car started fine.Warmed up less than 5 minutes, started to drive to work. Got approximately 2 blocks from home and the engine light and cruise not available warning came on. Drove another block and cruise warning went off.Amber engine light still on, drove the 15 miles to work. Seemed to run okay, but didnt try to push it at all, didnt try to go over 60 mph. Four hours later,at lunch,went out started, engine light still on. Drove around the block, parked turned off ignition. Drove 2 blocks to NAPA to see if they could pull the codes, they said to take it to the dealer....riiight. Back to work. Left again to go to the post office then back to work. All the time the engine light is on but car seems to run ok. Had to go back to post office, went in 2 minutes max, came back out started car, no check engine light!! Back to work, finished day. End of day, still no engine light, stopped by Auto Zone, pulled codes. P1111 and P0174. Ive read on here several different definitions for these codes.

P1111 - Manufacturer Control fuel Air Metering
P1111 is nothing to worry about.
P1111 ( all systems go)
P1111 Intake air temperature sensor circuit
Intermittant high voltage
p1111 is just a normal code... readiness code...

P0174 Fuel Trim too Lean (Bank 2)
P0174,is to Replace the Upper and Lower Intake Air Control Valve, O-rings and gaskets

and the guy at Auto Zone said it was the O2 Sensor, $439.99 for the part only.

Im so confused. No, Im not going to take it to the ***********, Im going to have my mechanic fix it, but he doesnt do Jags on a regular basis, ever really. So I need to know what to tell him and what part to get for him to replace.

 

Wow. No. Those are possibilities, but KISS. Start with small stuff. If you feel comfortable doing some basic DIY (it just involves using a screwdriver and a half hour of time, I promise!) then go to your local parts store, get a can of CRC MAF Cleaner, and clean off your MAF thoroughly. If not, ask your mechanic if he wouldn't mind spraying your MAF with cleaner. Don't use Carb cleaner, though. That will basically kill it. Have PepBoys clear all your codes after you do this, and see if it comes back. If it does, then look into other things.

When your MAF gets dirty, and can tend to create a lean condition. I'm not intimately familiar with Jags yet, but on BMWs O2 sensors also had their own code if they were failing. I'd think they'd throw a code, too, if they were the culprits.

Best of luck.

 

My experience with Ford products is that a lean code is normally caused by either a dirty MAF sensor or there is an intake leak. Like was mentioned, KISS. Do the easy stuff first and then go from there.

 

queenmb, you've probably read about the three main culprits for P0171/0174 code (lean condition) and usually it's been an intake leak, not 02 sensor. All the intake leak possibilities are simple fixes. Check the PCV hose for a split on the underside. The Brake boost hose for disintigration of the check valve and listen for the hiss from the IMTs leaky o-rings.

 

As they said. Do one at a time and step back to see how many problems you've solved. One item will fix most if not all of them.

 

Regina, this is your answer to your pm you sent me. I would have him replace them all if never done and be done with it or youll be back each time for each 1 of these very common vacuum leaks.
Bill

 

Thanks guys! Ill check those and let you know what happens. I may be back with more questions. [sm=smiley9.gif]

 

Brutal, excellent advice. If all three are original, do 'em all at once.

 

I own 1999 xjr and I am experiencing the same problems sometimes the car runs great ..it feels sluggish half the time.I am getting the 0174/0174 code and I also have checked everywhere for leaks.but I do hear a hissing sound coming from the throttle body area I cant seem to pin point.The car also hesitates when shifting from parking to drive it seems like there is a leak of some sort(pressure)..The hissing sound makes me believe its a vacuum leak..could anyone help please before getting molested by the dealer.I did a mass air flow and throttle body cleaning.What else should I be looking for?

 

Jimmy, get yourself some tubing (about 4 feet of it, possibly a little more). Now, stick one end of the tubing next to your ear and then run the other end near the throttle body. When you really hear the hissing, that will be the spot of your vacuum leak. Hopefully that will help you locate the leak and save yourself from a trip to the dealership.

 

Thank you...I also forgot to mention the valve covers are leaking as well.

 

Jimmy, it is very possible that the vacuum leak you are hearing is the valve cover gaskets leaking. That would be right in the same area that you are looking at. one of the hoses coming off of the intake feeds into the oil path of the engine. This causes the internals of the engine to be at a vacuum. You have a bad valve cover gasket, it will be sucking in air, leading to what you are hearing/feeling. The valve cover gaskets are not tough to do, just have a lot of interference you need to get out of the way to get the covers off.

 

thank you

 

I hope it is not a fuel pump OR COULD IT BE THE air flow meter? 0174? WHAT KIND OF TEST CAN I DO TO NARROW THESE PROBLEMS DOWN.?

 

still battling this 0174 out

question could it be my s/c ducks I hear they tend to cause a leak.?
I have looked everywhere for this leak and the vacuum lines seem sound.
any suggestions? and if so where is the write up for removing this part of the s/c?

cant seem to find it on jtis

 

yes and esoecially because those ducts are NOT solid, but 2 piece. They slide alittle in and out, and Ive had new ones leak worse than the ones I replaced. So yes, you should be able to spray the area and see if the idle changes. I prefer to monitor short term fuel trims with a scanner and check because its way more accurate than idle changes you can hear