Every thing I have tried thus far has not worked. New coil packs , plugs, fuel filter, fuel pump, IACvalve, fuel injectors, fuel pressure regulator.,MAF cleaning, all visible grounds cleaned and tightened.
NEED HELP

 

Welcome to the forums DoodleDandy1,

I've moved your question from General Tech Help to X300 forum. Members here with the same model will be able to help.

When you get a minute, 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

 

Have you changed the coolant temperature sensor?
Also the crank position sensor could be a likely culprit.
Along with the throttle position sensor.

 

have not investigated this solution (yet) but will do
Thanks

 

CTS is the easiest followed by the CPS.
TPS requires a special procedure I think.

 

Can you tell me more about the stalling issue? I’d like to understand how and when it stalls, cold engine, hot engine, Etc.

 

Hi DoodleDandy1,

Vee has asked a very good question - more detail would help us help you.

Steve has listed some very likely culprits, but as you've already discovered, simply replacing parts can lead to great expense but no resolution to the problem. With all the Jags on the Gulf Coast there should be a good independent shop in your area with knowledge of Jaguars. You may save yourself time, money and frustration by getting a professional diagnosis. A pro will begin by using a scan tool to interrogate the computers for any stored diagnostic trouble codes that may have been triggered by the stalling episodes. The OBD system on the X300 is primitive, but it can still often point in the right direction.

If you really can't bring yourself to visit a professional yet, you might at least visit an auto parts store and ask them to scan your car for codes. Write down any that are found exactly as they appear and post them here and you'll get plenty of help.

Having said all that, another thing you can check yourself is the transmission fluid. Low trans fluid has been associated with stalling while slowing to stop or make a turn, so it's worth ruling that out. To check it, drive the car for 15 minutes or more to heat up the fluid, park on a level surface, set the hand brake, and with your foot on the brake cycle through all the gear lever positions (PRND32), holding each position for at least 3 seconds to fill all the valve body passages, then return to Park and check that the fluid level is exactly even with the HOT MAX line on the dipstick. Do not overfill, and use only a good Dexron III substitute, such as Valvoline Dex/Merc (the blue bottle, not the red bottle Maxlife because its viscosity is too low), Mobil 1 ATF or Redline D4 ATF (not D6).

Cheers,

Don

 

Thank you Steve Thank you very much in the words of Elvis. So today I tested the throttle position sensor on a suggestion. tomorrow I will Test the Temperature Coolant Sensor. .By the way the TPS is functioning as a TPS should and I was pleased to see this.Voltage rise and fall smoothly.. And since you show an interest. Let me start at the beginning so you know the history.
this X300 began acting up a few months ago. the stumbling and stalling got increasingly worse. I thought maybe the fuel filter may need replacing after this I moved to replacing the fuel pump and that was a pain. the symptoms to decrease but this was still not the issue. I then decided to clean out each injector after checking fuel pressure which appeared to be above 35Psi... But I Replaced the fuel pressure regulator .All this done, I realized whatI would consider False improvement.so I decided to tackle the electronics by replacing all ignition coils, plugs and painstakingly tracing each lead from coils to ecu with ohm meter to eliminate all possibility of broken wiring . following this i replaced The IAC valve, cleaned MAF and Throttlebody as well, Checked for vacuum leaks as well as possible . I am retired , love this Jag and have time on my hands and enjoy a .challenge. but this is a complicated car giving me a run for my money. I even cleaned all noticeable ground points, replaced all O2 sensors. thus far this SOB is still stalling when driven in town.. It performs well over %)mph and highway driving, No trouble starting or restarting when stalled.. The only commendation following a shop visit and scanner was O2 sensor replacement . I damn near rebuilt the whole car already. The only system left to go is the tranny.
Love your input.

 

Hi,
My X300 became progressively unhappier. First, it would miss on occasion, then, It would stop running once it had been running for 20 minutes, or so (rather impractical on the Autobahn.), but would restart. Then, it eventually would not restart. I replaced the throttle position sensor, crank position sensor, MAF sensor, coolant temperature sensor, ECU, coils, and fuel filter, and cleaned the throttle body. Three shops (local independent, then the Jag dealer, then an independent who claims to be a Jaguar "specialist"), spent many of my € "troubleshooting", cleaning ground points and failing to tighten the nut on the main ground, replacing the fuel pump that was working fine, replacing the new plugs I had just installed with the wrong plugs, binning my K&N air filter to replace it with a paper filter, swapping the front and back O2 sensors wires by accident... but did not solve problem. In the end, replacing the new aftermarket coils (purchased from Limora) with used OEM coils from a donor car solved the problem. The suspicion is that the aftermarket coils were delivering unexpected results to the ECU, which then shut down. Testing your car with coils from another that is running well may be worthwhile. Fingers crossed!
Michael

 

The TPS on my car bench tested absolutely fine, but would cause my fuel trims to lock in at 10.2. I replaced everything. Only until I replaced it, did the problem go away. It’s a part that often causes random issues.

Another common part that causes random stalls is a failing crankshaft position sensor. I’m not aware of any way to positively bench test this part either, although I have not experienced a failing sensor, many on this forum have as a quick search will reveal.

If you can read your fuel trims, a high LTFT might point the TPS to be faulty.

If the LTFT is close to 0, then I’d try the crankshaft position sensor.