I have just purchased a 1999 XJ8 at auction as a project. (I also have a 98 XK8, so I am familiar with some repair issues). The XJ8 was purchased in "won't start" condition, so I don't know the history on the car. When I turn the key, the engine turns over, but won't fire up (start).Here is what I can tell you:-Car is stock from what I can tell, no modifications. It is an AJ27 engine.-New battery (always charged when working on car).-New spark plugs.-New Crank Position Sensor (under the car).-I have AutoEnginuity software with Jaguar expansion. The only trouble code I have is a U1135 for a rear driver door module fault.-I can turn the key, all electronics appear to operate, the car tries to start, turns over, turns over, turns over, won't fire.-I have put oil in the cylinder as mentioned in nikasil washed cylinders, no change. (still no spark, so I don't think it is the problem).-I have 40psi at the fuel rail, I can hear fuel pump in trunk run.-I removed each ignition coil and spark plug (separately), installed plug in connected coil, grounded, but no spark at all (I also tried this in the dark just to be sure, nothing).-I have 12v at each ignition coil.-I just swapped ECMs from a 99 XJ8 with the same options and part number, still won't fire.No matter what I have done, the results are the same, and I still have no spark at all. I would be glad to provide any other details to help diagnose. I feel like the car is so close to starting.Thank you.
Country: United StatesMake: JaguarModel: XJ8Year: 1999Engine: AJ27 4.0L
See first post.
Hello and welcome to justanswer.comDid you check for injector pulse with a noid light? Did you try starting in neutral? Do you have an rpm signal when viewed on live data with your tool?
Thanks for your reply. I went out and bought a noid light. 1) Injector pulse: NONE on any injector.I plugged noid light into a fuel injector connector, turned key to start car, no light flashing, and no steady light, absolutely nothing. I tried all other injectors, same result, no light. In an effort to confirm the noid light was functional, I installed on my XK8, turned car over, and light flashed while running, so I know what a proper result should look like.2) Neutral start: I put car in Neutral, and attempted to start, same result, no spark, no injector pulse, just kept turning over.3) RPM Signal in live data: Yes! I actually have a reading. It fluctuates around 144 - 150 RPMs when attempting to start. I also saw where there was a "Crank Request" live data option, and that goes to "1" as soon as I turn the key.What is next?
Ok thanks for the additional info. The reason I asked if the engine would start in neutral is because the park/neutral switch on the trans sensor is an input to the ECU to energize the injectors and coils. We may have a problem with that sensor. Go in the passenger rear of the engine compartment and you will see some connectors clipped near the top of the trans. You are looking for the 10 way black connector and both the black/pink and red/blue wires and you should have ground on both sides in both park and neutral. Another possibility is a security problem. The vehicle security may need to be reset with an immobilization program only available with the Jag factory tool.
Thank you, XXXXX XXXXX be on to something here. Here are the results of the tests for ground for that connector you mentioned:In PARK:Black/Pink wire has solid ground.Red/Blue wire has NO ground.In NEUTRAL, same as PARK.Black/Pink wire has solid ground. Red/Blue wire has NO ground.What is next? If it is removing the center console, that's not a problem as I have removed the console from my XK8 in the past, so I am familiar with removal. I also have a spare J-gate shifter assembly from my XK8 that I know is good. Thank you.
Ok this usually indicates an issue with that switch which is on the trans. To be sure jump the wires to see if it will start.
Ok, I jumped the black/pink and red/blue wires, and reconnected the plug. No change.
Double check that we have a ground on both.
I created jumper with a paper clip and connected the black/pink and red/blue terminals together. I have ground on both terminals. This time, I did not reconnect the plug. I attempted to start as I have been before. Turns over, no spark, no injector pulse.
Ok then we really have ruled out everything except the ECU itself or the security will need to be reset with the Jag factory tool. This reset is called an immobilization.
Ok, thank you for all of this help. I think it is always good to rule out as many issues as possible. As I mentioned, I also had another ECM (same part #) that I swapped. I just swapped it again, same result. This would point even further to the immobilization that may need to be done.In my past experience (with my 98 XK8) I had to have the key re-programmed, but when that issued happened, I was not able to engage the starter, just the guages and basic electronics.Thank you again. If you don't mind, I will leave this question open for now, just in the event of further questions. I will check in with the local Jaguar dealer to determine their availability, and will keep you updated.
Ok sounds good. Keep me posted.
We can make sure we have all the powers and grounds to the ECM just in case. Click on the link for the wiring diagrams.
Hi Richard,I have made an appointment to have the car towed into the local Jaguar dealer to see what they can find. I will keep you updated and will accept answer in a few days, once resolved. Thank you!
Ok let me know how you make out.
12 years at a Jaguar dealer as technician and shop foreman.
Thank you for all of your help. I had my 99 XJ8 towed to the Jaguar dealer. They performed an immobilization reset, and the car started right up! Thank you!
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Thanks for the update. I am glad I was able to help.