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I recently purchased a 2006 XJR in a non-running condition - engine cranks but does not catch. Price was right. Most importantly, it does have the navigation system which allows me to explore the option of upgrading it to the JagDroid system. My '04 XJR does not have navigation. So, fix the '06 and sell the '04 is the grand plan and by doing so I gain another 50K miles (the '06 has about 107K miles and the '04 has 158K)
Now it is time to put my skills to work to see if I can revive it.
After hooking up my Pico scope to the crankshaft position sensor, I was not getting any signal. Feeling excited, I replaced the sensor, did get a signal but the car stil did not start.
I next hooked a fuel pressure test adaptor in the fuel line by the fuel pressure sensor (regulator). I got around 55 PSI when I was cranking but still not catching. I tried cranking a few times but the pressure kept going down (I could hear the pump running). I relieved the pressure and tried again but now I am only getting about 24PSI and nothing more. I obviously have a fuel delivery issue with potentially other issues as well.
I removed the back seat and removed the passenger side tank cover where the fuel level sensor resides. The fuel looked ok, not stale and there was no apparent contamination, discoloration or foul smell. Yeah, I should have checked that first but whatever....
I did hook up the scope on one of the coils but I could not get a definitive trace to indicate that the coil is trying to fire... so I still need more work there.
Having recently worked on a vehicle that had sat for years with *identical* (a Ford Explorer) no starting symptoms, the cause was seized injectors. After removing the injectors and professionally cleaning them, I was able to bring the truck back to life.
Anticipating that I may actually have to work on the injectors I was looking through the workshop manual to see what the disassembly process is for removing the injector rails and there is no clear cut answer. The charge air coolers are in the way and if you look at page 2086 of the power train manual, the process of removing the air charge coolers is to remove the supercharger which I know is not a trivial job before the air charge coolers can be removed.
So my simple question after setting up the context: What does it take to remove the injectors for inspection/cleaning? Is there a writeup somewhere that I am missing?
I will be tackling the fuel pressure issue first to see what is going on and will verify that I am getting a signal to the injectors and coils themselves but I fear that I may need to get to the injectors before long.
I recently purchased a 2006 XJR in a non-running condition - engine cranks but does not catch. Price was right. Most importantly, it does have the navigation system which allows me to explore the option of upgrading it to the JagDroid system. My '04 XJR does not have navigation. So, fix the '06 and sell the '04 is the grand plan and by doing so I gain another 50K miles (the '06 has about 107K miles and the '04 has 158K)
Now it is time to put my skills to work to see if I can revive it.
-- snip --
So my simple question after setting up the context: What does it take to remove the injectors for inspection/cleaning? Is there a writeup somewhere that I am missing?
I will be tackling the fuel pressure issue first to see what is going on and will verify that I am getting a signal to the injectors and coils themselves but I fear that I may need to get to the injectors before long.
Thank you!
I had the same problem re-activating my 1984 XJ12 some years ago. I made up a lead to the injector with a push button switch and two crocodile clips. I connected the clips to the battery and the other end to the connector of the injector. I powered up the ignition to pressurise the fuel rail, then tapped the push button switch repeatedly. I could hear when the injector freed up by the change in sound. Got all 12 cylinders working, when it would only previously run with starter spray. Perhaps the start (ether) spray could diagnose whether it is ignition or fuel absent? I'm not sure this would work on the XJR, but I'm in the middle of removing my supercharger, and I wouldn't say it's a fun experience, so you might not need to do it if you can shock the injectors back to life.
Thanks for the comments. Putting the injectors at the bottom of the list for now.
I shot some starting fluid in the intake and cranked the vehicle. Nothing. Ignition does not fire.
Fuel pressure now does not go over 20PSI while cranking. Did replace the filter since the previous one had the Jaguar logo on it.
Clear codes and cranked. Three codes come back consistently
P2228: Barometric pressure Circuit low
P0069: MAP - barometric pressure correlation
P0335: Crankshaft Position Sensor circuit low
P0335 is strange - the sensor has been replaced and I do get a reading on the scope. Upstream wiring issue? God I hope not.
I went back to the CKP sensor and reseated it - the plug itself is marginal and needs to be replaced - it was not seating properly. Once I have done that and when through a few more cycles, the P0335 code went away. Ok, now, thinking, no CKP signal, no ignition so I went back and shot some more ether in the intake, cranked the engine and the engine did fire! Pressure still at 20PSI.
So, it looks like fuel pump for sure needs to be replaced. I may still have injector issues but one headache at a time.
I am familiar with the '04XJR fuel pumps but the '06 is different. Will look through the forum and see where folks are sourcing the pump from...
This is what I am working on - beautiful blue eye candy.
As I am thinking about, I know I saw the pressure go to 55PSI first time I checked it. Could instead of the pump, the fuel pressure sensor/regulator (pointed to by me in the second picture) be at fault sending the wrong signal to the ECM which then regulates the pressure to 20PSI thinking it is 55PSI. I wonder if there is a pin point test for the sensor....
Beautiful car!
You can buy a cheap bluetooth OBD II code reader and install the app on your phone and read all of the engine sensors, the fuel rail pressure sensor included. I have
, and it works well. If it corroborates the measurements you read on your gauge, then it's a problem with fuel delivery. I had a check valve go bad on mine that caused all of the fuel pressure to bleed off into the tank. There is a sticky on the fuel pumps where you should find the replacement pump motor if that has gone bad. Yours probably has the single pump while the predecessors had the dual pumps.
Last edited by Jacuar; 11-10-2021 at 04:26 PM.
Reason: weird url link issue
So I broke the connection from the fuel filter to the rail, blocked it off and measured the pressure right at the output of the fuel filter. The pressure came up to 70PSI after priming the ignition key three times. No issues whatsoever. So my suspicion is that the fuel pressure sensor/regulator thinks that 20PSI is about 55PSI and instructs the ECM not to build the pressure up. The fuel pump motor noise is noticeably different too - meaning, it works to build up pressure when the fuel rail is not hooked up (simulates the condition that the fuel rail does not register any pressure).
So my next step would be to source an FPR (recommendations on where to get one welcomed). A couple of pics on my test setup:
Last edited by Lagonia; 11-10-2021 at 06:18 PM.
Reason: Spelling
It looks like the part number is AJ87977 and can be gotten for around $50 + change + shipping and tax from eeuroparts or autohausaz. jaguarparts.com wants about $120 + ancillaries.
This is what a pulled out of the car - Ford part# 3R3E9F972 that fits several cars and can be had from Amazon for $25. The sensor that I pulled out looked that its been there for a while, quite possibly since the car was built. Would the factor purposefully put a Ford branded fuel pressure regulator? Then I realized, s**t, I can get one from ebay for less than 20 bucks!
Yeah, a lot of Ford components on these XJs. That one looks like the same as the normally aspirated XJ pressure transducer. I got a spare from an s-type.
Yeah, a lot of Ford components on these XJs. That one looks like the same as the normally aspirated XJ pressure transducer. I got a spare from an s-type.
I can't imagine NA and SC would be different sensors - this sensor just reports rail pressure and the ECM/fuel pump determine what to do - there would definitely be a difference there between NA and SC.
Parts Geek has these fuel pressure regulators for $58 (my 2006 VDP may need one). It is made by Eurospare. Other sources show FPRs as much as $130, one of these is made by some company called, "NTK". What is the difference in these? I wouldn't want to waste money on a more expensive one, but also wouldn't want to put something on my car that is cheap junk.
Parts Geek has these fuel pressure regulators for $58 (my 2006 VDP may need one). It is made by Eurospare. Other sources show FPRs as much as $130, one of these is made by some company called, "NTK". What is the difference in these? I wouldn't want to waste money on a more expensive one, but also wouldn't want to put something on my car that is cheap junk.
My research shows that Standard FPS 7 is a direct replacement - still pricey at $130 but available at my local O'Reillys. (Lifetime warranty). Since I have a functioning '04 XJR that has the identical part numbers for the fuel pressure regulator I will swap them and see if I am on the right track. Hopefully I can do it today after work.