Looks like the iCarsoft LR V2.0 works. Plugged it in and it found all the info on the car and ran the diagnostics. Now all I have to do is look up the P1251 code that it gave me that says Throttle motor relay off malfunction.

Joe

 

with help from icarsoft I updated the unit tonight and it works perfectly and the previous U and B codes are no longer there. Great unit.

 

Brand new to the forum! I posted this a few days ago in the general section about OBDII scanners, but just found this thread specific to XK8's. And there are recent posts here.

Does anyone have an update on recommended diagnostic scanners for a 1999 XK8 (convertible) in the US? I am considering getting both a conventional scanner and the Bluetooth type, since those are so affordable. I don't have any experience with scanners, just want one that will read everything I need to diagnose codes and clear messages. I don't think I need to see real-time data, but I am open to it if someone thinks that will be useful (see below for my problem). Also wondering if a conventional scanner is really necessary, if the technology on the Bluetooth ones has quickly developed and made those obsolete? (Although, I am not a tech guy at all, so something basic that WILL work is preferable to me than fancy stuff on a screen that might be troublesome.)

My car's issue: intermittent "restricted performance" message for a few seconds to maybe a minute, and ENG light stays on. Have had the shop clear the ENG light but it comes back. Usually happens during the most benign conditions like cruising down the freeway. Puzzling. Local shop that specializes in classic cars cannot figure it out. They did say there were "lean" codes on both sides. I had them do the dreaded fuel pump replacement (was showing low pressure around 30), no change. The car is virtually pristine, only 32,000 miles. I state this because everything on it is like-new, no rust, corrosion, or anything - all components still look like the day they came out of the factory, so whatever the problem is is not caused by corrosion-type problems. Most bolts have never been touched. Can anyone help point me in the right direction?

I have owned this car for 14 years and love it, but this problem has been plaguing me for too long now and nobody can seem to figure it out. Yes, the shop went through all the diagnostic troubleshooting and checked all the recommended items. Starting to cost a small fortune and getting nothing fixed out of it. Yes, have new air cleaner, fuel filter, fuel pump, fuel completely drained, entire fuel system gone through, and all other items related to restricted performance message checked. Note: not much difference in actual performance when the message is showing - perhaps some slight lack of acceleration, but nothing near the limp-mode dumbing-down of the engine that can happen. (But that's what I am afraid of and why I want to get this fixed.)

I'm at the point that I just need to be able to read and clear the codes so I can try to diagnose the problem myself, and if I buy a scanner(s), I want to get one that will also do anything I need in the future, too (for this car). Any help from the experienced and helpful people on this forum will be greatly appreciated! Please be specific about the type of scanner, model, plug configuration if that's important, software version to look for, etc., as I have zero experience with them. Also note, I'm not a mechanic but I am pretty good with a wrench and fixing things, just not the tech side of things and the more modern diagnostics. Most of my experience is old-school before there were scanners! Back in the carb days before electronic ignition and vacuum tubes were the latest and greatest. Ahh, the good old days when you could just pull out your screwdriver and adjust the mixture and be on your way...

 

Morning Jagareth,

I don't know if I'm experienced enough to give you a recommendation (I've only purchased my first Jaguar a month ago, 2001 XK8 convertible). Like yours mine had very low mileage, 62,000, and looked to be, and is, in great shape.

When I took it to get a smog check to register it the smog guy got a code P1251 - Air Mixture Solenoid Malfunction. Needless to say he didn't even bother to test it. I looked that up and found that it had something to do with either the wiring to or the actual throttle motor. I checked the wires and everything looked ok there.

I ended up buying 3 different OBD2 readers, including a bluetooth, but none of them worked on my '01 XK. My last purchase was a iCarsoft LR V2.0 that I bought on Amazon. It's specifically for the early XKs and XJs. It's a wired unit but seems to work well. You just plug it in, before turning the key to on, and it fires right up. Turn the key and go to select your make/model/year after it recognizes that it's a Jaguar and run the diagnostics.

My problem was that my car kept throwing messages "ASC not available", "Failsafe Engine Mode" and "Trac not available" and the "Check Engine" light would come on every so often. I'd end up having to shut it off, start it again and again until the messages and lights went off. The first thing I found on here was to check the battery. Mine was almost new but it seems whoever the prior owner went to for it didn't tighten the terminal clamps up enough. Once I did that it seemed to make the messages go away. Then I put the iCarsoft scanner on it and got the same P1251 code but this scanner indicated that the Throttle motor relay off was malfunctioning. I put a new relay in and now everything is working fine. Well, there is an issue with the trunk/boot opening button but I'm pretty sure it is the broken wire issue in the trunk, but that's not a big problem at this time.

Again, I'm by no means experienced in Jaguars but you might check the battery, both running and off. From everything I have read these cars, as well as anything built after about 1965, has a ton of electronics and any lack of power on start up will make their combined electronic brain go bananas. Another reason for the lack of power at startup could be a bad or going to go bad starter motor pulling too many amps at start up so that the rest of the car's electronics get starved and poof there go the codes/messages/lights.

Not sure if this will help in your situation but there's my $0.02.
Joe

 

Thanks, Joe. I hadn't considered the battery. While it seems to be functioning fine, it is about time for a new one based on age, so maybe I'll try that and see if it fixes the problem. It was on the list anyway, and that would be a huge bonus if the restricted performance went away so easily. (Although I have my doubts it will be that easy a fix - things don't happen like that often enough!)

Great to know about the scanner issues. That helps me narrow the options down. Thanks.

 

Many of us have discovered the magic of a trickle/maintenance charger. Regular use for us does seem to keep the gremlins away.

 

A trickle charger was recommended to me by the shop, too. I'll look into that. I have always disconnected the battery when I knew I was not going to drive it for more than a month. That worked well for many years when I stored it over the winters in Alaska. The irony is, now that I have moved it to the dry desert in the SW US, and I can now drive it year-round, now it suddenly has been acting up. Not a single problem for 13 years of intermittent driving, now a year of multiple little things popping up when I drive it regularly. Either it hates the new weather, or it is just getting old and cranky like I am!

Speaking of batteries, during COVID, I couldn't get back to attend to the car for too long. Both batteries in the key FOBs drained completely flat. They have not worked since, despite everything I have tried - fresh batteries 3X, careful and diligent cleaning of the inner electronics, numerous reset attempts in the car, and I even replaced the entire control module in the trunk. I have checked everything, right down to the wiring all the way to the antenna. Nada. I still can't believe that BOTH FOBs would go bad at the same time simply due to the batteries going flat. Anyone have ideas about this one?

 

Well the iCarsoft LR V2.0 has turned out to be very frustrating. The monitors for the CAT, EVAP and CCM will not clear. I've been trying to figure out if it can diagnose a bad O2 sensor but can't find it anywhere in the manual. I've tried calling the contact phone number on the website but it does not work. I've sent emails to their tech support address but only had them tell me to update the software, which I did. Oh, it does state "theft detected - vehicle immobilized" which it obviously isn't since I can drive it.

I've pretty given up on this thing and am looking for another suggestion.

JOE

 

I’m far from an expert, but I’m learning from the forum that often a fault code will not clear until the fault is resolved and / or a complete drive cycle is completed.

that said, the reason I bought the LR v1 rather than the more expensive LR v2 is that as far as I could tell, the extra features of the LR v2 only would apply to cars way newer than our X-100’s.


there are faults that my LR v1 won’t clear, such as the headrest, but I’ve always thought that was because I haven’t fixed it yet..

Z

 

iCarsoft tech support has always been a joke. I have had my iCarsoft i930 scan tool for nearly nine years and while it has indeed paid for itself, I would never consider it to be a great device. Forget about getting any real help from them if you have questions about your particular scan tool's performance....

 

HI Z,

Part of the problem is there are no fault codes. My original problem was a throttle motor fault but I fixed that. After clearing the fault codes I now can't get the monitors to reset. I've watched so many videos and read so many threads about "drive cycles" but so far none of them work. It's pretty hard to drive at the speeds suggested for the time suggested on CA freeways.

JOe

 

I'd agree with you on the joke that they call "customer support" Jon. The phone number doesn't work and the last I heard from them via email they asked me to send them the file that it produces, which I did. That was at least 2 weeks ago. Since then radio silence. So I now have a $200+ paperweight.

If anyone out there knows of a scanner that will let me know if one of the O2 sensors isn't working, and doesn't cost $800, let me know. For now I guess I'll just have to start pulling the sensors and replacing them. I'm not sure where else to go. Well, I'll start that once they take the stitches out of my hand.

Joe

 

the only time I did talk to the iCarSoft customer support it was in hopes of downloading software upgrade(s). Once they told me that Apple Mac wasn’t supported I knew I was on my own.

truthfully, the forum is more help than than even the best customer support I’ve found for any automotive product made for our cars.

your hand: OUCH ! I hate to ask as it’s none of my beeswax, but what the heck happened ?

it’s no news to you that our fingers have more nerves than those “other” body parts with the reputation for extreme sensitivity.

i found that out when i burned my hands badly trying to get a flaming couch out of my house before everything around it caught fire.


Z

 

Hi Z,

The forums are helpful, sometimes. Other times I run into conflicting opinions or too many acronyms, lol.

I have (had) something called dupuytren's contracture. It hereditary, my dad had the same thing. It causes one or more fingers to curl over as the cord calcifies. One "solution" is injections of something called Xiaflex. I had a few of those (the last ones hurt like crazy) but it comes back. This time I had the whole cord removed. Looks like hell but it doesn't hurt any where near the injections. But now I have a 2 week wait until they take the stitches out and then I'll have physical therapy, mostly to keep the scar tissue from causing the finger to bend more.

Joe

 

The injections sound pretty bad ! Hope your recovery time flies by as fast as the wind.

Z

 

What were you hoping the code reader would do? It can't show you codes that don't exist and it can't set drive monitors for you or drive the car at the speeds you need to on the freeway. The only thing you could do with it is read the live data from the O2 sensors and see if they make sense. I would do that before investing time and money in new ones.

 

Best wishes for your hand to recover quickly and fully. I can relate -- way back during my football career I completely ripped a tendon from the tip of my left ring finger. They had to slit the finger all the way down into my palm to find the end of the tendon in order to reattach it. While dexterity therapy helped with the recovery and healing process, I still have very little feeling in that finger and I cannot completely straighten it. I have learned to live with it and just work around that injury.....

 

Hi Dibbit,

I guess I'm in need of two things, a scanner that can tell me if one or more of the O2 sensors are bad and causing the monitors not to reset, and then a definitive "drive cycle procedure" to reset the CAT, CCM and EVAP monitors. There are so many procedures out there, from just driving the car to starting the car cold then allowing it to warm up, with the a/c on full blast and the rear window defogger on, with no electrical equipment on, then driving between 45 and 55 mph for an unknown amount of time, driving over 65 mph for at least 10 minutes, then coasting to a stop, or coasting to under 20 mph. Who knows what magical procedure will pop up next. I've tried most of the ones I've found, some of which are a little hazardous on the freeway, and so far I still get INC when I plug in the scanner. It is, to say the least, very frustrating.

Joe

 

Thanks Jon. I hear what you're saying. The Doc said the finger won't be perfectly straight but he did say I shouldn't have any problem pulling back the clutch lever on the bike so I won't have to speed shift my way through the gears :-)

 

Some basics: if you warm the engine up and park does it idle smoothly and does the OBD status show it's running CL (closed loop) on both banks as it should?

If yes, what are the fuel trims?

BTW EVAP can be a pest as it needs a non-full tank but also one not too empty (it's to do with avoiding such as sloshing around).

To a fair extent the PCM (aka ECM) is going around a loop often looking at sensors as on this page and controlling actuators accordingly.
https://web.archive.org/web/20220409...com/page02.htm

Your exact list of codes with causes is on JagRepair.com - Jaguar Repair Information Resource I expect.