Hi,
I don't know if my precedent post have been lost, I apologize to the administrators if they feel I send two times the same thread. I have a 2003 X-Type automatic 3.0 4wd. who has now 146000 kms. Since one month I have an irritating problem, the car runs fine and then pops a warning " Cruise control not available" with an amber light and the yellow check engine warning. Due to this the engine runs in protected mode and I can't go more than 3000rpm. Since then all six sparks plugs have been changed, the oil, oil and air filters changed, the transmission liquid and level checked and we have added a product in the gasoline tanks to clean the injectors. I have asked too to changed the contact on the brake pedal for the cruise control and it was o.k. . Today we have checked again the car because the same problem is ocurring again after some days without any warning. The codes sent by the E.C.U are P0171 and P0174. The guys from my garage have told me that it could indicated with the two lambda probes and an exhaust gas test is scheduled for next week . Does anyone here can tell me what can be the cause of this problem? The batttery is new and of the correct voltage (12V), I use only BP 95 gasoline because a Jaguar specialist has told me that cheap unbranded gas can damage the engine. Thank's for any help!

 

MarcJR, Codes P0171 and P174 are common codes for the X-Type. These are saying that there is an air leak in the intake. We have what are known as the "big 3" when it comes to this problem. The Big 3 consist of the PCV hose, the brake booster hose, and the IMT valve o-rings. All 3 parts are fairly cheap to replace, so, you may want to just spend a few bucks to get all 3 to ensure you don't have future issues. The PCV hose is easy to inspect. If you look at the intake coming from the intake filter, just to the left of the tube going to the throttle body, you will see a hose about the same diameter as your thumb. Remove this hose and check the underside. If the hose is smooth, then I can almost guarantee this hose will be cracked/split. If in doubt, it should be replaced with a ribbed hose. Second check would be to look at the top of the engine and there should be a hose sticking out the top of the intake that runs over to the brake booster. In the middle of this line is a "football" (oval piece about 2.5 cm in diameter). If you take your thumb and rub this, do you get some of it to rub off in your hand. If so, it needs to be replaced. This part is known for cracking, leaking to a leak. Finally, if you are standing in front of the car and lean forward, placing your hands on the intake, where your left hand most likely ended up should be 2 black disks about 10cm in diameter. These are the intake tuning manifold valves. There is an o-ring that seals the valve to the intake. These will develop a leak. You can replace one o-ring really easy. The other one, you will need to undo the two screws, pull the IMT valve out slightly so you can grasp the o-ring. Then you can stretch it slightly to pull it over the end of the valve. Reverse for install.

If you still have an issue, then we need to go further into troubleshooting. BUt, these 3 things fix 99% of the issues that you are describing. If you are still having issues, write back and we will give you a check to do so you can find the leak.

 

 

Greetings Thermo,

Thank's for your answer. I have already checked the Big three but they were all o.k. Apparently the problem is with my two lambda probes... That's was the answer of a Jaguar's specialist. Do you think it's another possible problem?

Best Regards