Hey everyone here is my problem. car runs fine when you drive normally but hit the gas to go fast and it stutters like it is going to stop. I have changed the fuel filter and cleaned the K&n airfilter but it still persists. was going to clean mass airflow sensor but it looks clean and I thought i could hurt it so I am waiting to see if you guys think that is my next step. I have a 2004 X-Tyle 3.0

Thanks in advance

Bill

 

How many miles on it? Could be a mildly fouled plug, or could be a vacuum leak. I'd start there since it's easy. Get her up to tmp and open the hood, if you hear a hiss track it back, likely just a hose, there are several write ups, Thermo has written up as have Dennis Black, search the later and he has pictures of all the usual suspects for vacuum leaks. But no worries sounds minor.

 

I agree Sidewalkman....but what im not figuring is why are you not gettin a check engine light or anything? Or are you? And yea milage would help.

 

I have had bad plugs cause this issue several times. If you are going to replace the plugs, you'll need upper intake gaskets....and I highly rec. replacing the lowers while in there. Add in the IMT o-rings if they are hard also. Inspect the brake booster check valve for leaks/deterioration.

My bet is that the plugs are junk.

 

Maybe bad gas? Dunno, does that even happen anymore like it used to back in the day with gasoline?
I have a Ford van and it does the same thing, but I know what the problem is....one of the "banks is running rich"....the CEL on the van has been on for a long time but it only does it in like 5th gear up a hill, so I don't bother with it The van has 125k and is paid off so I'm not throwing money at it!
Sounds similar to yours, but you have no CEL coming on.
Try the plugs, gas, vacuum leaks first. That's good advice.

 

I had this exact problem with my XKR. Car would run quite normally until you pressed the loud pedal and then it would stutter, feeling exactly like a misfire.
Car had new plugs, so I new it couldn't be those. Problem turned out to be the mass air flow sensor. It took me 10 minutes to remove and clean with a little alcohol and a fine brush. The car was then returned to warp speed just as normal.
Worth a try. Hope this helps.

 

I'm experiencing the exact same problem after replacing spark plugs on my 04 X-Type Manual.
Where is the Mass Air Flow sensor? And how/where do I clean it?
Thanks in advance.

 

The mass air flow sensor is usually located in the air in take housing. On the XKR it sits just after the air filter and before the throttle body. I imagine on your X type it will be similarly located. It will have an electrical connector coming from the side. To clean it I removed it from the air intake and using some alcohol and a fine brush gently wiped the internal probes. You might expect these to be dirty, not so. Mine did not look particularly grubby. Once replaced, the difference to my car was amazing. I read somewhere Jaguar charge £160 for the diagnostic test, and do not bother to clean these units , but replace as a matter of course. Hope this helps.

 

When I clean the Mass Air Flow Sensor on all our vehicles I buy a can of CRC 05110 Mass Air Flow Sensor Cleaner. Anything else will ruin the sensor. Give yourself 2 hours for this project. Gather some clean paper towels, can of WD-40, either Philips screw driver or tool to loosen/tighten the screws/bolts to the Mass Air Flow Sensor, flat head screw driver or metal putty/scraper. Locate the Mass Air Flow Sensor (usually in-line to throttle intake, after air box) and spray some WD-40 just on the screws (helps loosen without stripping heads), but just on the screws, if too much sprays out, use a towel to clean up. Let this sit for a couple of minutes. Disconnect the Mass Air Flow wiring harness connector (gentle not to crack the tab), move it out of the way. Next, unscrew the screws/bolts, but remember which screw/bolt came from which hole. Use the flat head screw driver or metal putty/scraper to pry free (gently) the Mass Air Flow Sensor. Set the Mass Air Flow Sensor in a clean dry spot and immediately go back to the open hole. Screw back in the screws/bolts to the same hole and use a clean paper towel to block the hole from dirt/foreign material. Shake your can of CRC 05110 Mass Air Flow Sensor Cleaner and with holding the Mass Air Flow Sensor, spray the sensor part (should be a metal wire) down. It is usually good to do this over grass or an old rag/towel. Give it a couple seconds and repeat. I do three coats. Lay the Mass Air Flow Sensor down on a clean paper towel to dry for a good hour (longer is best). Once dry, reverse the steps to install. Start it up. I personally after starting it up, turn it off after a few minutes, then pull the ECU fuse for a few minutes. Replace fuse then start her up. Should clear out anything and run based on the clean Mass Air Flow Sensor.

Remember, all this is try at your own risk.

 

Also, you should only clean your Mass Air Flow Sensor when you are a few miles away from an oil change. The chemicals in any Mass Air Flow Cleaner will get into your oil and not do any good. You have to find the Happy Medium of letting air flow through the sensor, but then change the oil before the chemicals full get mixed around in the oil.

Also, another option to help with the throttle body deposits, with the opening for the Mass Air Flow Sensor open, use the can of CRC 05110 Mass Air Flow Sensor Cleaner and stick the nozzle in the opening (direct the tip of the nozzle to where the throttle body would be) Give a couple sprays (if you can spray with one hand and move the throttle with another, you can get a mist of this on the inside of the throttle body to soak the deposits). The can of CRC 05110 Mass Air Flow Sensor Cleaner is plastic safe so it will not ruin any plastic hoses. Read up on a can of Throttle body cleaner, that stuff is NOT plastic safe and WILL ruin plastic and hoses. That is why all pictures of cleaning a throttle body have the throttle body removed. After a couple sprays let the hose air out, but make sure no dirt/foreign objects make their way into the hole. try to let this air out the same amount of time the Mass Air Flow Sensor is drying from its cleaning. When you go to start the car, you will have a heavy hesitant sputter, after trying to start, stop for a couple seconds. Start again and that should do it. Like I said, I pull the ECU fuse for a few minutes and then install and start it up. Should clear all things out to run based on a clean Mass Air Flow Sensor.

Remember, try at your own risk.