Hi All,

Not sure how to express this, but I have experienced something in my yr 2000 xkr that I am not sure how to diagnose.

Under firm acceleration, the engine seems to hit a wall at about 120km/h, where it seems to either not be able to change gears properly or the engine is having an issue- but I am not sure what it is, and I have difficulty putting it into words.

I had it looked over at the mechanics, and they changed an injectors and it certainly runs very smooth all the time until the above situation arises.

I find it difficult to explain to them what it is, and also, I am not sure if they want to risk replicating it to figure it out either.

It is my hope someone will know what this is or have any ideas/experience with it! Thank you kindly in advance.

 

Did your mechanic check for any codes? That is the first thing that I would do.

I would also suggest that you invest in an OBDII reader that will work with either an Android or iPhone. It will save you money in the long run. If the car generates any codes, the forum members can decipher them for you before you start replacing parts using the guesswork system.

 

Thanks StuG, there were no codes reported by the specialist jag mechanic, other than the injector issue, but I will purchase one of those OBDII readers anyway, as they are quite good value!

I was hoping someone had experienced the same- it doesn't effect the day to day enjoyment, but it is very annoying to know that the issue exists when you push it towards the limit. (And not have to get too far down the guesswork rabbithole!)

 

Maybe a blocked fuel filter / failing fuel pump (the 2nd one I expect).

 

If you worked on cars before the computer age, this type of problem was usually one of two things: 1) the engine can't breathe, 2) the engine is starving for fuel.
I would agree with "JagV8"

 

Have a look at this thread to check if both your fuel pumps are working:-

https://www.jaguarforums.com/forum/x...el-pump-85882/

 

+1

 

Awesome, I will check the fuel pumps via the linked thread when I am home this evening and report back.

 

Just a long shot, but I would also make sure that your throttle body plate is opening FULLY when the accelerator is pushed to the floor... they are known to need adjusting.

You do mention FIRM acceleration... does it go over 120 km/h if you are not hammering the pedal?

 

Howdo, I just bought an xkr with paramount performance add ons, it did the same until I cleaned the air filter and squirted the electric contacts on the airbox and throttle body. It pulls fine now.

 

Yes, it does. It only gets into a rut if it is being pushed hard.

 

Those paramount parts are from England right? Did they get ordered and installed here, or is there a local specialist that uses those parts in W.A.?

 

If the fuel and air delivery is good, defective plugs/cops can also cause the engine to sputter at full load (from a certain rpm).

 

Ok, fuel pump test is done, and both pumps are working well.

Next in line to test:
-Clean air filter, squirt the electric contacts on the airbox and throttle body
-Fuel filter blockages
-Defective plugs/cops
-Ensure the throttle body plate is opening fully
-Engine warnings (once reader arrives)

 

Congrats on the pumps, keep us posted, this is a good one.

 

You say it runs fine unless you're pushing it HARD. Are you saying that it goes over 120kph when not pushed hard? If so are you certain you're not getting a "restricted performance" light that sets a 3000 rpm limit that triggers an ignition interrupt? You can easily run 160+kph and still be under 3000 rpm's if you keep you're foot out of the throttle.

I just had to ask<G>

 

Sorry General, i'm from Exmouth, England! The paramount stuff was fitted before me . Dyno 413 bhp ! i'm not sure that it still is though , but it is tasty .

 

A high speed miss is a good indicator of bad plugs. You already looked at the other possibility, low fuel pressure and restricted intake. You could also run a bottle of fuel system cleaner through it, especially if the performance is enhanced still using the original flow injectors. High power engines need high flow injectors.