The engine malfunction lit up yesterday morning, and since then the car has sputtered a couple times.

See codes below. Seems like the Mass Air Flow sensor, right? I bought some mass air flow cleaner than I'm gonna try to spray in there - think that's a good first step? Is it easily accessible?

Thanks in advance!

Codes:
P0171
Fuel trim bank one condition
The powertrain control module uses the oxygen sensor to calculate the air/fuel ratio of the engine. The computer has recognized a rich or lean condition in one bank only.
Probable causes:
1. If bank one and two codes set together suspect fuel pressure or Mass Air Flow sensor.
2. Oxygen sensor defective
3. Ignition misfire-repair
4. Fuel injector problem


P0174
Fuel trim bank two condition
the ECM has detected a rich or lean air/fuel ratio condition on bank two.
Probable causes:
1. If bank one and two codes set together suspect fuel pressure or Mass Air Flow sensor.
2. Failed H02S21 (Heated oxygen sensor - Bank 2 sensor 1)
3. Fuel injector problem
4. Engine mechanical condition


P1111
Intake Air temperature (IAT) intermittent high voltage-low temperature condition.
ECM detected the IAT input voltage was intermittently high- Temperature low.
Probably causes:
1. Open circuit to IAT - Check connector.
2. Failed IAT
3. Open circuit condition

 

99.999% you have a vacuum leak. Do a quick search for the P017x code for solutions. Also, you cannot use generic P-code charts for P1xxx codes, these are manufacture specific and Jaguar doesn't define P1111 the way you found it online. Ignore P1111 and look at the P017x codes only.

 

It sounds like a vacuum leak and is not uncommon with these cars. I am attaching a procedure that worked on xk, xj & s-type and see no reason it would not work on your x-type. http://www.gusglikas.com/images/Auto...otos/P0171.pdf I had a leak on my s-type and I substituted the water with CRC Throttle Body cleaner (2-cans) and began spraying systematically http://www.gusglikas.com/AutoRepair2...VacuumLeak.htm I hope this helps.

 

Holy cow. That's one helluva fix! I'm pretty handy with engine work and done a lot of it, but I don't have any of those high tech tools .

With the holidays coming up and tons of family coming in town, I won't have time to get to this for a few weeks. Think the car will hold up (driving to and from work for a few more weeks) before I fix it myself? How much MIGHT something like this cost if I take it to a Jag dealership?

 

Not sure what it could cost. It is a matter of finding it and then making the repairs. It is at times a simple process to find it using the CRC spray approach. Get the car to operating temperature then spray your intake and vacuum hoses and see if the engine stumbles, when it does you found a leak.

 

First, don't overthink this or you can waste a lot of time pursuing the wrong avenues and still not solve the problem. Vacuum leaks on AJV6 X-Types are very simple and come from one (or more) of three places. Inspect the PCV hose for cracks. It leads from the front cam cover to the intake manifold. Inspect the IMT O-rings for leaks and finally the brake booster vacuum line and one-way valve. All of this will take you only 20 minutes with nothing more serious than a screw driver. If the holidays are in your way, you can wrap tape up the pcv hose or the brake booster hose with black electrical tape until you can get the replacements. The only leak that will take a little more time is the IMTs. Even those you can temporarily seal until after the holidays, then replace later.

 

Great, i'll start poking around in there and see what I can find. Anyone have some engine pdf's that show those components?

 

This is a link for a download of the Jag JTIS manual https://www.jaguarforums.com/forum/s...ead.php?t=4172 I have nothing on this car but I think this download will help you. Good Luck!

 

I had these same codes show up this morning on the drive to Nashville. Well, I didn't see the codes until I had a reader hooked up, but the warnings came on while driving there....

As a new owner, I figured to first see what I could just find, rather than go find a shop...and these forums sure were a great help.
I bought a can of the cleaner, removed the sensor and cleaned it well, especially down in the deepest part of the sensor. Looking at that with a bright flashlight showed it was pretty dirty- as was the inside of the air duct leading on back. I removed that and cleaned it as well. It seems that a lot of the dirt is from the connection to the valve cover (is that an egr valve?).
After the whole thing was completely dry, I reassembled the items and restarted the car. The warning lights all went out in about three seconds. No problem since.
On top of that, it seems that the throttle is a bit more responsive at the very first touch compared to what it was prior to cleaning. Might be my imagination, but something changed....

 

Tim, try cleaning your mass air flow sensor first. Because you are getting it on both banks 1 and 2 (P0171 and P0174), that is normally a problem that is upstream of your throttlebody, but downstream of your mass air flow (MAF) sensor. I would also do a quick check of the flexible boot that is between the MAF sensor and the throttle body. If you get a rip in that, it can cause what you are seeing. BUt, normally you don't have a problem with that.

 

My codes came back today. No different driving or anything, just suddenly appeared. Once again I cleaned the mass air flow sensor, but this time I took the entire air duct out and cleaned it thoroughly, as well as the breather pipe.
The throttle body intake flapper was pretty gunked up, so I got carb cleaner after that and it looked good quickly. Mass air cleaner after the sensor, and let things dry once again.
I tried to start the car about a half hour later, and it cranked but would not fire. This went on for some time...wait for fresh air/dry and then crank. It would not fire.
About the fourth time, I (as I know you shouldn't) held the throttle wide open and cranked. It fired, and ran real rough, then died. I let it set again for about 10 minutes and cranked it again. It started, but ran rough. I ran it out on the road for about 15 miles, and it smoothed out nicely. But the CEL remained on, and the Reduced Performance came back on.
At a light, it ran very rough, and then stalled. It started again easily, but the CEL remains on, although now the RP notice has gone out.
Does it seem most likely there is a very small hole somewhere? I've not found it, but from responses on this thread it seems likely. I guess I wonder if cleaning all the gunk out from inside the bellows or the rest has opened up more of a hole than might have been there....maybe plugged by the gunk?
I'm interested in your thoughts!