My 97 XJR seems to be in limp home mode or something. It seemed to start exactly when it turned over to 79,000 miles. It starts, runs fine, up to 1500-1700 rpm. Then acts like it isn't getting enough fuel to go any faster. Light acceleration allows the car to get up to speed, but it isn't going to turn over 1900-2000 rpms even when up to 45-50mph.

 

Ok, I have a LM 327, and the app on my phone. I am getting several codes.
P0332, P0300, P0304, and P1316.

The car won't stay running now. I suspect the fuel pump as my first check? Also, how do I clear the ECU? The ELM allows me to clear the log, but from what I can tell, not the codes.

Any advice on where to start MUCH appreciated.

 

Can't offer help, but very interested to hear what you find is the culprit.

How's the car been since then? If I recall this is the same one you and I were both looking at from up in NY?

I know my Actron reader can clear the XJR codes, so maybe just another reader than the one you have?

Good luck!
.

 

Thanks Al! Yes, this car was the one listed by the guy in NY. It was there a very short time. It seems to have spent most of its time in Florida. Sold new in Colorado, but was very low miles when registered in Florida. It had that banging noise in the rear, that turned out to be shock bushings. Major job, but worth it. Looking back, I really don't think it needed shocks, only those crazy bushings.

I'm sitting here now, searching on my first course of action, presumably fuel pressure. Looks like its a possibility that the fuel pick hose can come off on these cars. It really does now act like its out of fuel. I can't imagine it being contaminated fuel, as the that is in the list of things to check under code P0300.

Will keep you posted. Seems a great car. Has acted flawlessly for about 8K miles. I made it back to my business, where I work on my cars, so for now, no tow bill.

 

Hope the dropped hose is all it is. That would be a relief.

I had the same rear bushing issue with the 97 I bought too. I went ahead and replaced the shocks too, as it just seemed more cost effective in the long run.

I agree, major job, but was worth it.

I need to replace the shock bushings up front too at some point. They don't rattle or anything, but I can see that the top bushing is started to deteriorate. That of course will be a MUCH easier job and less costly. After the rear shocks, replacing the front shock bushings will be a walk in the park!

.

 

Ummm Since you have a code reader, i would start by looking at what the code means and start from there, it looks like you have a misfire yes? p0304 is misfire on cylinder 4 right? solve that one first.

 

As far as I know the XJR (and the V12) don't have the 'dropped hose' issues because, with their dual fuel pumps, they don't have the hose. The internal tank plumbing is different. Worth verifying before going thru a lot of labor. I think JDHT/Jaguar Classic Parts catalog clearly shows the tank internals

P0300 and 0304 are misfire codes, as mentioned. Worth fixing. Coils are a common problem, for one.

Near as I can tell P0332 is a knock sensor failure. This could be important, as the knock sensor (with the ECU) retards the ignition timing.....which could easily account for your sever loss of power. Personally I'd go after this code first. You have 2 knock sensors on the left side of the engine block. Start with a simple visual inspection: are they plugged in?

I think P1316 suggests cat convertor damage/failure. If a cat converter was plugged up it could certainly cause low power.

Cheers
DD

 

Sounds like a plugged fuel filter to me. Had very similar symptoms on a Chev van at work. At least that's cheap and easy to do.

 

Crank position sensor may be at fault here, I was getting a weak signal from one I was lookin at a few weeks ago, making it feel like it was hitting a limiter at about 2500rpm.

Changed out maf sensor,pressure reg,ecu, from my own car still no change, tried cps and hey presto!

If your fuelling checks out cps is well worth a try 😜

 

These are the things I had hoped to hear! Yes, I have a code reader, but feel that something else caused the codes. Number one thing to check is contaminated fuel. I really don't feel that this is my problem, as I drove it about 20 minutes, when it suddenly began to act up. Like the fuel pump went bad, or the fuel pressure regulator. I would love to check fuel pressure, but just like my 89 XJS, it has no port to do so. But that for certain seems my best option. On my XJS, I plumbed in a tiny fuel pressure gauge under the hood. It is so small, it looks as though it could have come on the car. Not very hard at all. I just put a T in the fuel return hose, and can see exactly what fuel pressure is as quick as I can get the hood open. I had read in another thread of the came condition, and the problem didn't go away until he replaced all 4 02 sensors.

Thanks for the tip on the fuel line. Seems if it were that, the car wouldn't run at all. It will run, just not very well. The plugs have about 7K on them, so feel reasonably sure that isn't it.

 

BTW, both knock sensors are plugged in. I asked about this when I first bought the car, as the check engine light came on....on the way home with it. I hate replacing parts just for the sake of changing parts just to see if I can find the problem. Advice of this forum told me that these sensors rarely go bad. The PO had the octopus hose changed, so the supercharger has been off at some point. I feel that something is amiss in that as well, because I found two hoses that aren't hooked up, and the cruise doen't work. We have only put 7K on it in over a year, and the car seems to operate flawlessly, so it hasn't been real high on my radar mostly because of this 6.0 with a 5 speed going into my XJS absorbing all of my Jaguar energy and patience, lol.

 

A little frustrated this evening. Loosened the return line from the regulator, and very little fuel came out when turning on the switch. Loosened the supply side, and fuel would go everywhere with turning on the switch. So, felt I had a bad fuel pressure regulator. I took it off, and no fuel in vacuum line, and using a vacuum port, could pull vacuum till my pump maxed out. Not sure what the fitting is, but appears I am headed to a hose company to see if I can get fittings to mount a test port or gauge, and get some idea of fuel pressure.

Before I started working on it, just for kicks and giggles, I started it. It fired up immediately, and even would rev to 2500-3000 rpm. But as soon as I allowed it to idle, it shut off, never to start again. I'm thinking I don't have a fuel supply problem, but won't move to next step until I find out what fuel pressure really is. It acts like it is out of fuel.

 

I had a 'rev limiter' effect appear once on my XJR, I couldn't see any faults but it was cured by chance after charging up the battery whilst it was out of action. More recently I had an intermittent bad running which I thought was contaminated fuel or lack of pressure. After much messing, it turned out to be corroded pins on the ECU connection. Cleaning them with contact cleaner, NOT WD40, cured the problem. Just a suggestion.

 

I'll check that! Thanks!

 

Well, haven't been able work on it until today. I can now confirm that it isn't fuel pressure. I put a gauge on it, so I could know for sure. It has 40 psi as soon as the switch is turned on. I tried starting it, and it fired right up, but then quit after about 30 seconds. Next up is cleaning the throttle body? Those pins? How can I check the crank position sensor?

 

whats the easiest way to clean the trottlebody on our xjr? from top or bottom ? how did you do yours?

 

I just tried to remove my throttle body from the bottom this morning but ended up giving. You have to twist your arms a few different ways to get to some bolts that need to be removed. .
Also the convulated hose is a pain to remove. That's where I gave up...

But if you wanted to tackle it, it is doable as posted on Jag lovers
Welcome to Jag-lovers - Members Photo Viewing Page

 

oh christ, i tried to reach up last time when i was under the car, seems difficult lol

 

I tried and failed as well


Cheers
DD

 

lol damn what about from the top? im guessinf its more difficult?