Hello I have an 2003 Jaguar S type and when I Accelerate at 3000rpm it jerks I change the Mass air flow still having the same problem does anyone knows maybe the problem to fixed this issue??????

 

Welcome to the forums FortMyers239,

I've moved your question from General Tech Help to S-Type forum. Members here with the same model will be able to help.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some information about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

You are going to need a diagnostic code reader, otherwise you are just throwing parts on the car, hoping to solve your problem.

Auto parts stores here is the US will often pull fault codes for customers at no charge. Get this done and return here, post the actual and full code (e.g. P0300) and I am sure we will try to lend a hand in getting your Jag sorted.

 

Thanks for replying back I have several different code

Codes

 

DTC guide for you.

 

Quite the list, but don't panic. Some of those codes are higher priority than others, so some can go on the back burner for now. Details here:

http://www.jagrepair.com/images/Auto..._OBD_II_R2.pdf


P1000, for example. That's just a monitor readiness code, and means various OBD self-monitoring functions have not had enough time to run since the last time the codes were cleared. Don't worry about it at all.

P0445 and P0447 refer to the evaporative emissions control. The list does say these faults can inhibit "adaptive fuel metering", but I don't believe that would cause the symptoms you're seeing.

P1532 and P1549 refer to the two intake manifold tuning (IMT) valves. It's difficult to imagine both failing, so I'd be leaning towards a common root cause, such as low input voltage.

P0102 is one of the big 'uns, as Al Bundy would say. That code points to a problem with the MAF sensor. You mentioned you've already changed it. What brand did you install? Many forum members have reported problems with aftermarket brands. A new OEM replacement is kinda spendy, but I'd be willing to gamble your hard-earned money on a used OEM replacement, such as you might find on eBay or from a wrecking yard.

Another possibility. Take a look here, at figure 03.1:

http://www.jagrepair.com/images/Elec...al%20Guide.pdf


Look carefully at the five items being flagged. Both IMT valves, the two EVAP valves, and the MAF sensor all get power through a common point. Follow the power source for each item. You will end up at figure 01.7, fuse F37 in the front power distribution box. Make sure that fuse is fully seated and that both prongs are gripped firmly by their respective sockets. After that, you will see that fuse gets power via relay R5 (EMS control relay) in the same panel. Try swapping that relay with another known-good relay of the same size.

If the fuse and relay are no help, you could have one bad component amongst those 5 items fed by fuse F37. The bad component could be drawing excess current, but not enough to blow the fuse. You end up with low voltage to all 5 components on that circuit. Try unplugging each item one at a time, clearing the codes, and see what faults return. You will get new codes due to something being disconnected, but the computer will substitute stored values and hopefully the other 4 will not set set codes. This is a free and relatively easy method to isolate a faulty component.

 

Almost forgot, see post #32 in this thread for a known problem area that could affect the MAF sensor:

https://www.jaguarforums.com/forum/s...2/#post1934812

 

Also clear all codes and drive the car and see what comes back. Some of those are probably historic codes and may not be current errors.
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One or more of those codes are inducing "Restricted Performance" mode, which is why you experience the "Jerking" at 3k rpm. Take a look at the info/message center on the instrument panel and it should be declaring "Restricted Performance" at the time. It will not rev over 3k in that state.