Fritz Frieden
 

I have three Jagars, 1999 Vanden plas, 2004 XJR and 2009 XF. I live in North Carolina and have been a Jaguar fan for many years. My first Jag was a 1952 Mark VII. I bought it in 1960. I bought a1966 420G in 1979, a 1988 Vanden plas in 2001 and a 1987 Series III XJ6 in 2017. I generally do my own work except when a lift is needed. I have a problem that I can't seem to fix on my 1999 Vanden plas. The restricted performance light is on with the ignition switch on even when it's not running. Sometimes it shows CEL 352,355 and 358 which points to coil pack wiring. Sometimes after complete warm up it runs fine on the highway but will go into restricted performance at an idle. This all started when I let it sit for about a month without starting it. Prior to that I have no problems with it. I have replaced coil packs, spark plugs, ECT (engine coolant temperature sensor) and MAF sensor. All this with no change in behavior. Any ideas would be appreciated.

Welcome to the forums fritzfried,

Good to have you with us. I've moved your post from the end of my 'guidance' thread to a new Intro thread of your own so all members will see it.

The possible causes in the Jaguar DTC lookup for those codes are:
1. ECM to ignition module primary circuit open circuit, short circuit to ground, high resistance
2. Ignition module ground circuit open circuit, high resistance
3. Ignition module / coil failure

Follow this link https://www.jaguarforums.com/forum/xj-xj8-xjr-x308-27/ to the X308 forum for help, advice and information. The 'HOW TO' thread at the top is a good place to start for information on regular issues. You can also use the US Lower Atlantic Region forum by following this link https://www.jaguarforums.com/forum/u...r-atlantic-66/ to find other members in your region.

Please read the guidance for new members ( https://www.jaguarforums.com/forum/n...ned-up-241802/ ) which answers many of the most frequent questions about getting started.

Enjoy the forums.

Graham

Welcome to the forums.

Welcome aboard.

Welcome to Jaguar Forums fritzfried,

Good to have you with us.
Enjoy the forum.

If you haven't done so already you should add your car details to your signature to help others to help you.
If you need help with getting around and using the forum follow this link for some help Forum Help

Welcome to the Forums.

Quite a fleet you have dealt with. My 1st car was a 1954 MK VII, in 1968, should have kept that sucker.

Good luck with the XJ8, I dont know the answer.

Hello, Fritz,
Another member with Deep Jaguar history!
Welcome to the forums from ElinorB.
(';')

welcome to the form - enjoy!!!!

Thank you all for your input. I'm still fighting this VDP. When I start it, it hits on all 8 for 15 seconds then it goes into restricted perforrmance with no CELs. If I let it idle for 15 or 20 minutes, the restricted performance light goes out and I can take it out on the freeway. I can drive it 80 mph no problem until I come to the off ramp and stop at the stop sign then it may or may not go back into limp mode. Sometimes, not always, I may get CELs p0352, p0355 and p0358. I know these indicate coil pack wiring but that doesn't explain why it will run after warm up. I have replaced the coil packs, spark plugs, MAF sensor, ECT sensor, air filter and cleaned the throttle body with no change in behavior. I'm starting to think ECM and I have the breakout for pin voltages on the ECM but I can't figure out how to actually measure them while it is active. With all the Jags that I have owned, this is the first time that I've been stumped this bad. I have a good diagnostic tool that allows data stream display. The only thing that's different from my 2004 XJR is engine coolant temperature and that's why I replaced the ECT sensor. The 99 shows 128 degree C. and the 04 shows 99 degree C. Again if any of you all think of anything that I can do further, I'd appreciate your input.. Thanks again to all of you.

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