Hi, i have x type 2007, 2.5.
I am facing issue since i bought this car a month ago, i changed coils and problem solved 80%, that time when i tried to go above 3k rpm it started jerking and slows down on road, same happened during idle mode, i changed the coils and this issue almost fixed but now it's again jerking like "bhubhak, bhubak frequently during idle or when i start accelerating, issue disappear slowly when speed increases gradually. please help

 

Your engine is oprating in "Restricted performance Mode". You need to get the OBD codes read and post the numbers. Once we know the numbers, we can help with diagnosing the performance problem.

 

It shows MAF error but i am not sure does it needs to replace MAF sensor only OR throttle cleaning as well.

 

It wouldn't hurt to do both. However, like was siad, post the code NUMBER(S) you are getting. That is the easiest and most accurate way for anyone to advise you. You said you have MAF issue. How to come to that diagnosis?

 

Codes are necessary to really nail down the issue, otherwise everyone is speculating and grabbing at ideas that could cause this to share and help............like me! I had a similar issue when my plugs were not gaped correctly. Need to be gaped at .052, if I recall. Also no double fire or multi-prong plugs. Just simple NGK Laser Iridiums is all you need.

If you need an OBD device, check out Blue Driver. It is what I have and it works well.

 

2003 x-type, replaced upper, lower intake gaskets, valve cover gaskets, booster vac, and PVC intake hose. Throwing no codes at all. My acceleration is very weak getting to highway speed from ramp, have trouble climbing hills, trouble getting to speed for 2 lane hwy passing. These are all power and acceleration issues I think. The car has a 3.0, 128 k miles. I'm a first time jag owner and this is a project / hobby car. Any ideas for this? The car is primarily being driven at about 8,000 feet in the Rocky Mountains.

 

Have a look at (long term) fuel trims in the hope they reveal something.

 

1. Quote:

   Originally Posted by JagV8

   Have a look at (long term) fuel trims in the hope they reveal something.

Now I'm thinking MAF sensor, O2 sensors, checking again on vacuum lines, anything in fuel system with this? This was a continuous reading through driving conditions. I see the reading should be taken at idle and at 2500rpm. Will do that.

 

Let us know what you find.

Jerking when the MIL flashes would be severe misfires (causing cat damage), but with no MIL flashing... let's get data.