Hello everyone. My name is Scott and I am a new member as well as a new (and very happy) Jaguar owner. I'm happy to have found this forum and hope you'll accept me as one of you. Mine is an 03 X-Type with the 2.5 with 85k miles. It's a beautiful and exceptionally well maintained Jag of which I am the second owner. Recently I have noticed a significant drop in MPG from about 22 to 15-18 depending on where/how I'm driving. I do use premium gas. Can anyone share with me tips on what to look for regarding possible causes for this drop in MPG or ways to improve it? Also, what are you getting? PS: Thank you, you've already helped me diagnose and repair one issue. My check engine light came on and a scan revealed the codes for left and right bank too lean. It was a cracked nipple on the in-line check valve on the vacuum line leading from the intake manifold to the power brake unit.

 

How soon after the repair did the mileage drop?
How many tanks of gas have you used since the mileage drop?
Is there a noticeable change in engine characteristics?

 

Quartz, MPG initially dropped as soon as CEL came on. It has not improved, at least not yet, since the repair, as I suspected it would. I have only filled the tank once since the repair. I am using the computer as an MPG reference, but in my experience it has proven to be reasonably accurate when compared to the mathematical computation of MPG. Also, along with MPG drop, engine performance was down when CEL was on, as well as error message "cruise not available". All problems disappeared after repair was made, except the MPG returning to pre CEL level. Oil level is between low and high. Has fuel injector cleaner or fuel filter replacement helped you? Or anyone?

 

Engine performance should be down with the CEL on. Computer goes into "limp mode" for safety.

Dirty fuel filter would most likely cause performance problems, not low mpg...

I might try some good quality fuel injector cleaner and a good, fresh tank of high tier premium fuel. Drive it for an hour or so and don't be afraid to mash the gas pedal during your drive. Clean that crap out and see how it goes...

 

Scotti, welcome to the forums. As you are finding out, we are a different group here and like it that way. So, enjoy the site.

As for your current issue, I would tell you to try disconnecting the battery negative post for a minute and the reconnect it (this forces the computer to relearn how the engine runs). It may be that it has learned how to make the engine run with the fault and it is still trying to straighten itself out following the fault.

Next, use a bottle of fuel injector cleaner from a manufacturer that is not who you buy your gas from (ie, if you buy Chevron, do not get the Techron gas treatment, etc). The reasoning behind this is that using the same manufacturer gas treatment is not going to fix anything as they are just upping the quantify of detergents and if those detergents are letting something build up, adding more is not going to remove the blockage. By going to a different gas treatment, they will have a different mix of detergents and you stand a much better chance of getting rid of any blockage.

The other thing that I will tell you to take a look at is if you like to use your e-brake every time you park, lift up on the e-brake and pay attention to how it feels. If you are feeling the very first part being extremely easy and then it suddenly gets harder, you may have a frozen rear caliper. You can confirm this two ways. You can take the car out for a high speed run (65 mph on a highway for say 5 minutes) and then immediately pull off somewhere and feel the center of the rims. If one tire is hotter than the rest, that caliper is freezing up on you (I have noticed that some X's have a problem with the e-brake lever not releasing all the way, leading to a dragging caliper). Please keep in mind that the front wheels should be slightly warmer than the rears as they do more of the braking. So, compare more side to side than front to back. Granted, if the back caliper is as warm or warmer than the front. PROBLEM!!!!! The other way to check the rear calipers is to remove the rear wheels and find the e-brake lever. If you look at the lower part of the lever (where it pivots), the lowest part has a pointy end. This sits between 2 bolts. With the e-brake released, the point of the lever should be resting against a bolt. if it is not, then the e-brake mechanism is freezing up and you have a dragging brake. if this is the case, I have a lot of experience with this and I have a few options for you.

Lets start with this and go from there. Lately I have been pulling around 23-25 mpg with some in town driving and a majority of highway driving. But, on a long run recently, I actually got the car up to 32 mpg. Only seen that once, but was shocked. Normally on long highway only runs, it will go to the 27-29 mpg range.

 

Outstanding Thermo!
Fuel injector cleaner - done. Disconnecting battery cable next and checking the e-brake. I DO use it every time I park. Thank you, will let you know...

 

Bravo Thermo, you are in the know. Left rear parking brake pivot is hanging up. It appears to want to stay that way as the return spring will not keep it back. Suggestions? I'll be lubing it and working it on my own until I hear from you. Thank you so much.

 

Scotti, atleast for the moment, you can simply use your hands and push the lever forward and allow the e-brake to not be engaged. Then you can drive the car without issue. Just have to remember to not set the e-brake till you do the repair. As for the repair, I see 2 options:

1) get a remanufactured caliper and get that installed. You can pick these up for around $110 or so. Then it is a matter of doing a 1 for 1 swap out and it will take you an hour or so to do. Do not forget to bleed the brakes when you are done.

2) On e-bay you can get a rebuild kit for around $15 and then you will need to get your hands on a 14mm pentasocket (a 5 sided socket). On e-bay they run about $20. From there, you can dismantle the caliper and rebuild it yourself. Pretty easy to do and is cheaper in the end. Your problem is going to lie where the e-brake shaft goes through the caliper body. That will rust and cause binding. Take a greenie or fine sand paper and clean up the surfaces and you should be golden. Do not forget to apply some grease to the outer edge to prevent water from getting back in and causing the same thing to happen. If you want a How-to on this, check out: https://www.jaguarforums.com/forum/x...fix-1-a-73065/

If you have any more questions, let me know. I think between this and the how-to, you should be golden.

 

Hey Scotti,
I have 2 good calapers off a 2003 X type. Also both E brake cables if you need them I will sell them to you cheap. Let me know. I have them already off the car and in a box. Wish you luck on your X . I love all of mine but soon one has to go. Running out of room to store them.

Best of Luck,

The Dr!

 

My left rear has begun dragging recently. I want to get a good look at it this weekend before throwing parts at it. I noticed that the e-brake is also only working one side so it may be an adjustment issue. E-brake cables are quite rusty too.