How long will I keep this one? - 1998 Jaguar XJR Content

TED_fiestaHP said:

  In many applications the coils just don't last, should be replaced along with the spark plug.  They get heat damaged and just don't last forever.  You might start with a fresh set of plugs and coils.

I agree. That was also a big problem with the Lincoln LS, I had one a few years ago, and that was one of the issues it had. Mismatched combination of various aftermarket and OEM coils, and not-so-great plugs, so it didn't run great. 

If I find that even one coil is bad, I'll order a whole set, and likely do sparkplugs at the same time, while I'm in there, unless they turn out to be almost new or something. I'm sure if one coil is bad, at least one or two others are on their way out.

It's actually going to be reasonably nice out today, so hopefully I'll be able to get the coil swap test done when I get home.

Also, tracking has updated on the brake switch; instead of arriving in the middle of the month, it should be here on Friday.

Still haven't done any testing, I had to do some deferred maintenance on the Prius yesterday that took way longer than it should have, and today it's raining, and there's no room for it in the garage. 

Also, I'm not sure how long I'll be keeping the car. Just paid over $400 to register it until July 2023, because Michigan bases registration fees on MSRP with no consideration for how old the vehicle is. That's only $100 less than I pay per year for my other 5 cars COMBINED. In the long run it's not like I can't afford it, but what I'm spending that money on is just completely stupid, and it doesn't sit well with me at all. 

In reply to JShaawbaru :

That's crazy. So they tax you at the new car price?  Y'all get freezing weather and this?  Why does anyone live in Michigan?

In reply to Stampie :

Not the tax, that's based on sales price, which makes sense. But the yearly tag for the plate is based on MSRP. Unless the car is 1983 or older, then it's based on weight. Clearly they need to update that cutoff... But then they'd make a lot less money. 

In reply to JShaawbaru :

Daaauuummmmm.

July is only 4 months from now, so they charge you $100/month registration fees.

Efff that 

In reply to Indy - Guy :

Love you like a brother but it's year 2022.  He got 16 months registration.

In reply to Stampie :

  I understand how you feel about fee's.   I bought a totaled mini cooper, the repairs were cheap enough, but then the fee's for the process of getting to the reconstruction title, the fee's don't make the car any better, but it's all part of the process.

Stampie said:

In reply to Indy - Guy :

Love you like a brother but it's year 2022.  He got 16 months registration.

Yep, which makes it $25/month, which in reality, looking at it that way, isn't horrendous. Then again it'll be put away in winter, so 3-4 months a year it'll just be sitting, and I'm not sure how much it'll get driven during the other 8-9 months, but the way my brain processes things, that $25/month doesn't seem as bad. The initial sting is starting to wear off, and I'm a little more ok with it.

If it had been $100/month though, I would have walked out of that Secretary of State office so fast, and had the car relisted for sale here before I even left the parking lot. 

Weather forecast is showing a little cooler today, but still workable, and "a passing afternoon shower". Hopefully it'll pass right by, and I can get outside today and get the coil swap test done, and see if the misfire moves.

I was thinking about any other possible causes of a misfire, and lack of fuel would be possible, except for the fact that I have the catalytic converter code, which implies there is unburnt fuel exiting the engine through the exhaust, so it's something ignition related, whether it's a plug, coil, or something farther upstream.

With the cat code and the flashing CEL, I'd change the coils and plugs first, then go from there.

Misfire, can be: coil / plug, fuel injector, or mechanical issue.  The least likely is a bad valve, lifter or valve spring.

     A good code reader should be able to give smooth running readings, for each cylinder.  A weak reading at idle that improves above idle could be a injector.

     Typical misfire is coil / plug, also the easiest to fix.

Good news and bad news:

• Good news, the problem is gone. The check engine light has disappeared entirely. There are no current codes. No misfire, no EGR, no catalytic converter.
• Bad news, I essentially didn't do anything to fix it. All the coils are the same. All the sparkplugs are the same. Also, uh, there's a new problem.

I started out by pulling the number 5 and 8 coil, and visually inspecting them. 8 looked a little worse, had some moisture on it, but nothing terrible. I pulled the 5 and 8 plugs as well, and they looked the same. I have pictures, and I'll upload them later. I put the plugs back in their original cylinders, and swapped coil 5 to cylinder 8, and coil 8 to cylinder 5.

Took it on a test drive, and nothing changed. I got a misfire in less than a minute, and during my first attempt at causing a misfire by accelerating aggressively, the orange AND red warning light came on, along with messages for traction control AND stability control failure. That all went away after a second or two, so I kept driving. The misfire continued to occastionally occur, as did the other weird stuff, which also included all the gauges dropping to zero/cold/empty like the car shut off. I pulled onto a side street and checked the codes, and lo and behold, ALL THE SAME MISFIRE/CATALYTIC CONVERTER CODES.

Oh, also, before that test drive, I apparently bumped the coolant level sensor loose, so when I started the car, it was VERY ANGRY and wanted to make sure I was aware the coolant was low. Thankfully it wasn't actually low, and I was able to get the sensor back in. I have no idea how it's actually attached, but it's in there.

So I drove home, pulled the coils again, and then swapped the plugs from 5 to 8 and 8 to 5. There was some moisture on the boot I pulled out of cylinder 8... So at this point, coil 8 and plug 8 were both in cylinder 5, and coil 5 and plug 5 were both in cylinder 8. The only other thing I did was run a shop towel down the number 8 sparkplug hole, in case that moisture I saw was part of the problem.  Time for another test drive.

At first, it was uneventful. I drove longer than the first entire test drive without even one misfire. But then the weirdness came back. Gauges all dropped, red and orange warning lights came on, and the traction and stability control warnings came up, along with the BRAKE warning light. Car was still running without any issue, and it went back to normal a second later. I think it also said something about "Failsafe Mode", but the messages went by so fast that I can't say for sure. This continued to happen intermittently for the whole 10 minute drive. It never lasted more than a second or so, and the time between events was anywhere from a few seconds to several minutes. It did have an effect on performance, but not a significant one, at least not the times that it happened, which were mostly when maintaining speed, and twice idling in the driveway when I got home.

There is a code, but it's just pending. P1797. I looked it up and it seems to be a communication issue between the ECM and TCM, possibly. Someone with an S-Type was able to fix it by simply cleaning the connection for the wires going to the rear of the transmission, but since my gauges are acting funny, I'm thinking that code is more of a symptom of a larger issue. It must be electrical though, I would imagine. I'll have to look into it more when I have time tomorrow, but for now, the car is at least more driveable than it was, although I don't plan on going on any long trips, in case the weird electrical thing starts happening more often, and leaves me in a non-intermittent failsafe mode.

As far as the misfire, the only thing I can think is that the moisture I cleaned out was causing an issue for the cylinder 8 coil/plug. The coil cover on that side isn't in the best shape, and is letting water seep in that probably shouldn't be in there. Two of the threaded inserts for the bolts were torn out of the valve cover, one of the bolt holes was broken off, and another broke off while I was removing one of the bolts from the threaded insert that pulled out of the valve cover. There was moisture all along the rear half of the cover.

The plan will be to epoxy those inserts back in,  possibly buy a new coil cover, and then use some RTV to seal it better at the rear to prevent water ingress. I'll probably do that tomorrow if it's not raining (if I decide to just keep using the damaged cover).

Pictures are added! Cylinder 5 plug and coil is on the left, cylinder 8 is on the right. Also this post is probably kind of a mess, and really long, but that's probably going to happen a lot, it's just what my brain does.

Grounds?

Grounds or a plug not inserted fully somewhere. Or, knowing British stuff, many different connections with corrosion on them. At least that's what id say with old British stuff 

Insure it and park it in detroit with the keys in it

  From the picture the plug gap looks different on those two plugs, but hard to tell from a picture.

       But it sounds like a electrical problem, once that is sorted, maybe the misfire will also go away.

          With several things going odd at the same time, would assume it is a weak ground, but hard to say.  Electrical issues can be tricky.

    You might try just adding another ground wire from the engine to the car body, would be easy and see if that makes a difference.

   Seems like a great car, minor problem that could be tricky to sort out.

TED_fiestaHP said:

  From the picture the plug gap looks different on those two plugs, but hard to tell from a picture.

       But it sounds like a electrical problem, once that is sorted, maybe the misfire will also go away.

          With several things going odd at the same time, would assume it is a weak ground, but hard to say.  Electrical issues can be tricky.

 

The misfire is completely gone, I did check the gap on the suspect plug and it was right at 0.048", which is the correct gap.

I did consider a ground being the issue, like you and Stampie said. I know Indy - Guy replaced the one from the battery to the body, but maybe another one is bad. It's definitely another thing to look at. 

TED_fiestaHP said:

    You might try just adding another ground wire from the engine to the car body, would be easy and see if that makes a difference.

   Seems like a great car, minor problem that could be tricky to sort out.

This.  Try adding a second ground strap.  This is what the rotted out one looked like when I had to replace it.  Couldn't find a thick one at any of the FLAPS.

The one I added may not be up to the task.

Edit: replaced when the starter was replaced.

Has the car been in the rain within a few days of those electrical issues? 

yupididit said:

Has the car been in the rain within a few days of those electrical issues? 

Sort of.  The idiot who sold him the car decided that he would give the engine a bath along with the exterior and interior detailing prior to his purchase.  None of the issues described were experienced before his purchase.  Could be something to it?

yupididit said:

Has the car been in the rain within a few days of those electrical issues? 

It was raining the day I picked it up, and it's rained more since then. That's one of the reasons I think the misfire may be moisture related.

Indy: there was another ground strap in the center console. Maybe I can find somewhere to put that one, even though it's not super thick either. I think I have one from my Insight that was actually pretty substantial, it might still be laying around somewhere. 

FOUND IT 

In reply to JShaawbaru :

Yes. I would install that strap too. Read my response above. Maybe just a good drying out would help too 

Indy - Guy said:

In reply to JShaawbaru :

Yes. I would install that strap too. Read my response above. Maybe just a good drying out would help too 

Ah yeah hadn't seen that one yet, you posted while I was writing mine. I didn't really think about it, but that could have been a contributor. That could explain why your wife didn't have the misfire just from normal weather, but then it appeared when I drove it. 

In reply to JShaawbaru :

Look under the cowl on the sides. There should be drains in each end. They get clogged, especially cars that are kept outside. 

Otherwise, your XJR is behaving normally lmao! 

Also, the MAF sensor is dinky and likes to give those reduced performance lights. Check if it's plugged in, clean it. Certainly do plugs, coils, and make sure the valve cover gaskets are done (leak easy). 

Oh and those hard lines you see running under the hood. They crack easy, check them but be very gentle lol. 

I've owned one of these cars since 2016. Hardly drive it though.