Hello All.

This is my first post here in quite some time. And I could really use some advice.

2 years ago (Oct 2014) I bought a 1997 XK8 for my wife (who grew up in Coronado, CA) from the original owner in LaJolla, CA (it's a Neiman Marcus Car) and promptly drove it back to Indianapolis (2200 miles) without a single problem. (it had 24,000 miles on it when I started home)

The car had not had the timing chain update - but we have a great shop (Hash Imports) that has a guy who's a wiz with these things and they did the timing chain a month later. (BTW - learned about that from you guys while I was doing the research before I bought it - BIG UPS FOR THAT!!!)

Last fall (2015) my wife drives it to school (she's put, maybe, 500 miles on it) and when she goes to drive it home, the yellow check engine comes on and gets on the LCD display "Stability Control Fail" followed by "Engine Fault" as it sputters to a stop. Being the blue-eyed blonde from Southern Cal that she is - she lets it set for a minute and then fires it up. No issues and drove it home..... (weird).

It does this off and on a couple times and back to Hash it goes. After clearing a bunch of codes and running it - they diagnose a bad throttle body.

Having learned my lesson from the Timing Chain Incident - and now fully armed with my SMG Barrett Catalog (LOVE these guys) - order a new throttle body. Hash swaps it out and she's running like a champ.

A month later, trying to drive out of the garage - SAME EXACT light and messages.

Now - (again, having learned from you guys about Jag's latent draw on the battery) from the very beginning whenever we knew she wasn't going to drive it for more than a few days to a week, we'd stick a battery-tender on it (I do the same thing with my NSX - although it's not NEARLY as sensitive as the Jag). We also changed the battery during the Timing Chain Incident.

Anyway - so having not made it out of the garage, I have it tilt-bedded back to Hash (just to be safe). Diagnosis - bad throttle body again. ...WHAT !?!?!

SNG says "Not likely, but always a small chance" and send me another throttle body (which, apparently was the case in that they refunded the first one). Hash thinks we need to change the kick-down switch at the throttle pedal and we do that as well. Back on the road she goes and life is good (the whole convertible thing just makes her day). OK - now we got it.

Another Indiana winter and the Jag sits in the garage, nice and warm under the cover and battery tender.

Now - about 6 weeks ago (after her driving a few times this spring) she goes to fire it up.... BINGO - SAME light and messages. Another tilt-bed back to Hash. A day later, they call to say that their getting all kinds of error codes and can't figure it out.... maybe something with the ECM. This time they're not fooling around and take it to Tom Wood Jaguar (who I bought a Lexus from earlier this year - good guys as well).

As I understand it, TW Jag thought we had let the battery drain enough (precisely ZERO chance of this) that the ECM & Throttle body simply had to be re-programmed - which they do... they drive it a couple of times and send it back to Hash. Hash drives it for a couple of days - then call me to come get it. Drove great for all those guys... drove great back to the house (precisely last Friday afternoon - 8/26/16). Battery tender applied with complete malice.

On Sunday, out of sheer curiosity, my wife fired it up in the garage. Idled for 5 minutes (too rainy to drive) and all is good. On Wednesday evening, when I got home from work, I did the same thing with the same result.

Last night - beautiful evening - let's go for a spin... top down, sweat jazz on the radio... and proceed to go PRECISELY 1/4 of ONE MILE..... when.... wait for it..... Lights - Messages- and TOTAL exasperation. At least I was able to coax back to the garage. The guys at Hash are going to KICK MY *** (or try).

So - after this long tale of British Car Woe - on behalf of myself, my wife, about 8 guys at Hash Imports and god-knows how many at Tom Wood...

I can assure you a bottle of your favorite beverage for any ideas or suggestions you might have.

Thanks a million. Terrence

 

I'd be looking for a bad connection - the crimps on the battery terminal can give problems (see if one of the terminals gets hotter that the other, as a start).

 

The 97's suffer from capacitor leaks in the ECU. Contact ASI in Tennessee and send it to them for testing, then repair if required.

Automotive Scientific Inc. | Quality Rebuilt Automotive Electronics | Rogersville, TN

 

+1

 

You need to get the codes read, and post them here or get them from your service record with Hash, if they are good they posted them on your receipt.
The current ones would be best since things may change otherwise CEL on isn't much to go on.

 

Hi.

I have said it before, and I say it again: Temporary faults are often caused by poor connections or chafing wires.

Try cleaning connections at the ECM, throttle body and TB power supply relay.

 

+1 on Oyster's comment. Get yourself a can of electronic cleaner and a soft brass tooth brush and clean up the connections. Also take a close look for any damaged bent or deformed pins. Poor contact will cause arcing and will degrade the connection. I have not heard of it in the 97's but the AJ27's from 99 on had a problem with the connector pins for the throttle body.
Your problem seems to occur after setting for awhile which would indicate some corrosion going on. Also while you are at remove clean and reconnect the grounds for the ECU.

 

To Everyone.... A Huge Thanks.

I'll run all of this by Hash and get back to you.

Thanks again.

 

1997 model, errors you are seeing, my money is on the ECM. My 97 did much of the same you are seeing. Runs fine then runs ****, runs fine runs ****, eventually will not run worth crap. I would have the ECM looked at. My money is that is your prombel. You car is going crazy, various issues. I your have checked the easy stuff, good battery, connections, etc, then I would look at the ECM.
I used these guys a couple of times, others here have also. They bench test it, if it passes they send it back to you, if not they fix.

Automotive Scientific Inc. | Quality Rebuilt Automotive Electronics | Rogersville, TN

 

mine pointed to being a TB issue, my shop put on 2, still same issues, errors messages, stumbling, running like crap, could not hit the gas and it move at all. I told them to get my orig TB back, and out it on the car. Got ECM looked at and was deemed bad, they fixed it, I put it in the car and it ran well. That was in 09. Cost like 250 plus shipping. I think anyone that has a 97/98 model should make this ECM a maint fix. They seem to go bad, just pull it and sent it out for a bench test, if it passes then you know it is good. If bad they can fix and you put it back in then if there are still issues you know it is not the ECM causing it.