When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
OK sooo... Here goes:
If you read my intro you know that I bought this '99 XK8 with a trans that had "quit pulling". After having it flat-bedded home I took it for a test drive & the trans shifted & the car drove out fine, driving it back & forth a mile each way from my driveway trying out the J-gate & everything for a total of 7 1/2 miles, but it started bucking at full throttle on the last leg (ignoring that for now). Then two weeks later it got hit by lightning: lightning hit the corner of my building & ran through the ground 6' & burned two of the wheels (r.f. & l.r.) & blew a hole in the out trans line. So I named her Electra - Lexie for short. To my surprise it still ran well & I think everything still works. So I serviced the trans flushing about 15 quarts of fluid out of it, installed the Trans-Go pressure reduction valve, made a dipstick/fill tube, & ran a steel braided hose to replace the blown trans line. I also replaced the lower radiator hose (typical rubbing on the fan shroud) & the belt, replacing the idler pullies with the metal aftermarket ones. Humm.. already had the metal pullies, as well as the aluminum thermostat housing & apparently a (fairly) recent water pump. The engine is quiet so for now I'm assuming the timing chains have been replaced (147,000 miles on the car). So i took it for another test drive & after the first mile I got "restricted performance" & the car went into limp mode with only 4th gear & limited RPMs. Found out the little coolant hose had come off the freaken' PLASTIC clip at the rear of the right cyl. bank, so I did what Jag should have done in the first place & threw the plastic clip away & pushed the hose over the tubing & clamped it down. Filled up the coolant - it had green coolant in it so I'm using that, & after filling it I noticed a note next to the cap saying to use only ORANGE coolant..
So for now two questions: 1) is the green coolant ok, & 2) How do I get rid of the "restricted performance" code? I've tried a hard reset twice. I don't have a scan tool yet..
I'll add that I've been through the first 300 pages of this forum & read over 1,000 threads - THANKS everyone here for all the great information I've learned!
Oh & also the PO said the top was leaking fluid at the windshield so I haven't tried the top yet, but I did buy the fittings to block off the latch hoses to do a manual release (but haven't done that yet). I also have new shocks, Baxter urethane for the front mounts, urethane upper control arm bushings, & upper ball joints ready to install when the car is back drivable.
I just want to DRIVE this thing!
Thanks again everyone,
P.S. I'm missing some plastic pieces on the engine & the cap on the windshield washer, as well as the dome light assembly & the caps for the Sport mode & other button, but I'm broke so I'll deal with those later...
Looking at the marks on the wheels, I'm amazed no electronic problems.
Originally Posted by Tha Driver
I also replaced the lower radiator hose (typical rubbing on the fan shroud)
It's posssible to fit that hose upside down, except the ends aren't identical and can cause what you found
Originally Posted by Tha Driver
Filled up the coolant - it had green coolant in it so I'm using that, & after filling it I noticed a note next to the cap saying to use only ORANGE coolant..So for now two questions: 1) is the green coolant ok, & 2) How do I get rid of the "restricted performance" code? I've tried a hard reset twice. I don't have a scan tool yet.
Jaguar changed from the green DOW coolant to MB spec just prior to MY2000 intro :
If it's green in there, then you can either stick with that or do a full flush and move to the newer spec. Note that the spec is more important (and a better guide) than the colour.
It's possible that the coolant reservoir has been replaced:- the superseding OEM units ship with the warning sticker.
You'll need to bite the bullet and buy a code reader. Even a cheap ELM327 clone (Amazon) to hook up with your mobile will read the generic P-codes.
Looking at the marks on the wheels, I'm amazed no electronic problems.
It's posssible to fit that hose upside down, except the ends aren't identical and can cause what you found
Jaguar changed from the green DOW coolant to MB spec just prior to MY2000 intro :
If it's green in there, then you can either stick with that or do a full flush and move to the newer spec. Note that the spec is more important (and a better guide) than the colour.
It's possible that the coolant reservoir has been replaced:- the superseding OEM units ship with the warning sticker.
You'll need to bite the bullet and buy a code reader. Even a cheap ELM327 clone (Amazon) to hook up with your mobile will read the generic P-codes.
Yeah I fully expected for the electronics to be completely fried, turning the car into a parts car. I'm REALLY surprised!
I read several threads on the radiator hose being rubbed through, & that was the case (groove rubbed into the hose) for mine. I trimmed the protrusion off of the fan shroud & added a piece of rubber there to prevent damage to the new hose.
I'll stick with green coolant for now then. Once I've driven the car for a while I may change it out. Thanks for the info.
I have a couple friends that may have acess to a reader. I'll work on getting them to bring it by.
Thanks,
Yeah I wasn't about to have to put the damn car on stands & check the hot fluid next to the exhaust pipe every time I wanted to check it. It's just STUPID of Jaguar not to have a dipstick.
Yeah I wasn't about to have to put the damn car on stands & check the hot fluid next to the exhaust pipe every time I wanted to check it. It's just STUPID of Jaguar not to have a dipstick.
Well, once you've fixed any leaks and filled it, there's rarely a need to check the level again until time to do a service. I still prefer dipsticks, but have learned to live without them. None of my BMWs have one, either.
Well, once you've fixed any leaks and filled it, there's rarely a need to check the level again until time to do a service. I still prefer dipsticks, but have learned to live without them. None of my BMWs have one, either.
Did that 90 degree bend cause any issues?
I'm 70 & "old skool" & I like to check all the fluids once in a while. The 90 degree is not a problem. Fluid seeks it's own level.
Well since I don't have a code reader & the car is stuck in "restricted performance", it's been sitting for nearly three months. I have been starting it once in a while & letting it warm up.
But I was reading in another thread & the guy said to turn on the ignition switch when doing a hard reset. Is that right? Will that clear the restricted performance code?
Thanks,
Paul
Filled up the coolant - it had green coolant in it so I'm using that, & after filling it I noticed a note next to the cap saying to use only ORANGE coolant.
If have flourescent dye added coolant looks green no matter original color. My orange Jag coolant and my pink Porsche coolant both look green.
OK well... time for a novel...
You can skip the novel if you just want to help me with the codes.
So... a year & a half ago (yeah it's been that long dealing with getting Lexie back on the road) I bought a Topdon code reader & plugged it into the car. Wouldn't read the car, or even go to the menu to do so. I specifically bought the Topdon because it said nothing about REQUIRING Wi-FI. It asked me for my email to continue, but I couldn't see any way to enter one. Then a friend came by & we were looking at it & he TOUCHED the screen to bring up a keyboard!!! WOW! There was nothing in the instructions that said to do that & I - having never owned anything with a touchscreen before - didn't even think of that. Anyway, he had Wi-Fi on his phone & we were able to download the latest updates, but then we still couldn't get it to accept my email. So I emailed Topdon & they registered my email. But I had to wait until I had Wi-Fi again to try it - but I still couldn't get it to work. To this day I still have not gotten it to read the car. So if you buy a Topdon just know that you *have* to have Wi-Fi & register it before you can do *anything*. But I have a cheap code reader now so:
All this time I've been starting it up once a month at least & letting it warm up, driving it a mile down the road occasionally. It had started having a miss when cold, that went away after warming up. Still in "restricted performance". Then the fuel pump went out. That's fixed thanks to the help here in my "Fuel pump confusion" thread. But now the car has developed a (two?) bad miss(es) now.
So my code reader says:
PO135 (02 sensor bank 1 heater circuit).
PO155 (02 sensor bank 2 heater circuit).
PO352 (Ignition coil B)
PO357 (Ignition coil G)
& of course P1000
P1646 (aux inputs)
& (Aux outputs)
I did change the plugs with ones that came with the car. The ones I took out were BKR5EGP & the ones I installed were BKR5ES-11. I have no idea if they're right. I did have a *little* oil in two of the plug holes, so I'll do a gasket set to take care of that in the near future. I also noticed one of the coils had no label - so not OEM.
What I really need at this point is the chart that lists codes, possible causes, & solutions. I thought I had it saved but I can't find it on my computer or here on the forum. Maybe a link on how to test coils & O2 sensors with a multimeter (or otherwise)? And which coils are B & G? BTW I've kept the battery up with a tender & dis-connecting it.
I appreciate all the help you folks provide here & I know you can help me straighten Lexie out & finally get to enjoy driving her.
TIA
Last edited by Tha Driver; Feb 20, 2026 at 10:33 PM.
You can check the Jaguar codes PDF which I hope is on JagRepair.com - Jaguar Repair Information Resource but I expect P1646 is another O2 sensor fault (bank 1, sensor 1 i.e. upstream). It's likely a wideband. Expect to change it but by all means check fuses/relays/wiring. If it's like my car it'll need a Denso of the right kind. Someone might say...
Without working coils, O2s and so on the car just can't properly do fuelling, acceleration, gear changes, etc.
With so many codes be sure your battery isn't low or tired.
Probably OK, since the car's not complaining about the downstream sensors, but check fuse #1 (30A) in the engine management fusebox, as that's the feed for all the sensor heaters.
Here's the codes explained:
Looking from the front towards the rear of the car, cylinder B is second from the front on the left, G is third from the front on the right.
Putting Lexie back on the road...
To my surprise it still ran well & I think everything still works. So I serviced the trans flushing about 15 quarts of fluid out of it, installed the Trans-Go pressure reduction valve, made a dipstick/fill tube, & ran a steel braided hose to replace the blown trans line. I also replaced the lower radiator hose (typical rubbing on the fan shroud) & the belt, replacing the idler pullies with the metal aftermarket ones. Humm.. already had the metal pullies, as well as the aluminum thermostat housing & apparently a (fairly) recent water pump. The engine is quiet so for now I'm assuming the timing chains have been replaced (147,000 miles on the car). So i took it for another test drive & after the first mile I got "restricted performance" & the car went into limp mode with only 4th gear & limited RPMs. Found out the little coolant hose had come off the freaken' PLASTIC clip at the rear of the right cyl. bank, so I did what Jag should have done in the first place & threw the plastic clip away & pushed the hose over the tubing & clamped it down. 
Filled up the coolant - it had green coolant in it so I'm using that, & after filling it I noticed a note next to the cap saying to use only ORANGE coolant..
I have been starting it once in a while & letting it warm up.
Anyway, he had Wi-Fi on his phone & we were able to download the latest updates, but then we still couldn't get it to accept my email. So I emailed Topdon & they registered my email. But I had to wait until I had Wi-Fi again to try it - but I still couldn't get it to work. To this day I still have not gotten it to read the car. So if you buy a Topdon just know that you *have* to have Wi-Fi & register it before you can do *anything*. But I have a cheap code reader now so:
