Yesterday I drove my ('97 XK8 vert) "up the hill" about 8 miles to get the VIN verified for new Kalifornia registration. It was the first time out of the garage in a long time, but she ran and drove very nicely. Combination of slow traffic and freeway with a couple of passing bursts and 70 mph cruising, then over to a local shop for smog cert. Nothing unusual....until: came out to move the car and all it would do is crank furiously. It will not fire up!

I don't have codes yet, but my dash says "ENGINE FAULT" AND "check engine". I poked around the fuses and relays but couldn't find anything obvious. One of the lead techs and the manager listened for the fuel pump, couldn't hear anything, crawled under the back and banged on the bottom of the tank. Nothing. I checked the FP fuse in the boot: it was fine.

I also tried disconnecting the battery ground for a few minutes to "reset" anything that would respond. Nothing.

SO....what the heck is keeping her from firing up????

 

Is it cranking extra furiously?

If so it could be borewash.

 

The battery is fairly new, so it certainly doesn't bog or lag. I thought about the wash issue, but I don't smell any gas at all (and I have a very sensitive sniffer). I've never had this happen, and there was no indication of any problem. Since it was driven to full temp and put through all the gears, motions, etc., what would cause the "wash" to happen. It was shut down in the parking lot for about 5-8 minutes.

 

You don't get MIL lights and codes for borewash so something else is going on here. Only way to tell for sure is to get a code reader and see what is reported.

 

Probably right. It's sitting outside the shop right now, and they will run codes first (I hope) to see what's up. I don't know this shop, other than it's close and they smogged my Suburban yesterday, and was set to do the Jag. Nice people, but Jag knowledge ???

 

The first thing I would do is connect a Fuel Pressure Gage to the Fuel Rail at the rear of the right side rail. This could help determine whether the Fuel Pump is bad:

 

OK friends, the story gets more weird. The shop called and said the Jag started the first try when they were going to do some testing. Hmmm.....okay..resets of something no doubt. But, since I had disconnected the ground at the battery I needed to drive it around for the smog test to work. No problem. Started right up, and I drove the same route except about 10 miles further. When I got back to the shop I left it running and they took it inside for the test with rear wheels on the dyno.

While waiting I hear the horn honking like the security system had been set off. 10 minutes later the tech comes in and tells me he can't get the car to start. An exact repeat of before: cranks like crazy, "check engine" light and "ENGINE FAULT" the little screen. This time, however, when I cranked it I could smell the fuel getting through.

This has to be some kind of security system glitch. The door locks have been doing the repeated lock-unlock-lock-unlock-lock thing. If the battery was low I'd suspect low power, but it's only a few months old. The windows work perfectly. I can lock or unlock with the fob, but sometimes the key in the door doesn't want to unlock the driver side.

So...what might be screwing up in the security system -- if that's what it is.

 

Check the two megafuses in the back of the trunk for clean/tight connections. Also check the heavy power cable that bolts to each fusebox for clean/tight connections.

And next time it happens do the fuel pressure check after cranking (just depress the shrader valve and check for a strong pressure stream)...do not rule out an intermittent fuel pump.

 

Here's a crazy thought: While reading WhiteXKR's info about the Realguages, I remembered that my low coolant light had been on for the last few times out. I had repaired a crack in the reservoir a few years ago, and now it is leaking just enough to lower the coolant level after XXX miles. I have not filled it because I want it low so I can pull it out and replace it.

So, the question is: does this affect my ignition system by sensing the coolant is too low after running at full temp, and forcing me to let the car cool off or fill the reservoir?

 

There is no interlock with the reservoir to prevent starting, only a low coolant message. The most common cause of no running after a long sit is a fuel pump meltdown. After sitting a long time, they can pull too many amps trying to turn and melt the commutators. This is the reason for all the comments on checking fuel pressure. Early models also have a software glitch that allows overfuelling if the engine is run briefly and shut off. This overfuelling washes down the cylinder walls, dropping compression to the point it won't start.

 

OK. The shop manager thought my idea was dumb anyway. It started up fine this morning, passed smog, and restarted when I moved it and closed the windows in the shop lot. I'm going to pick it up in a few minutes, bring it home, and start checking grounds and contact points of lines.

The fuel pump health still concerns me, and the shop owner said it could be an electrical component heating up while driving. But it never shut down...just no restart with plenty of juice from the battery. But the door locks continue to lock-open-lock...and the fuel door wouldn't pop open. I'll also try the hard ground/drain of the system so it clears everything.

 

Hard reset cures all! I was having alot of no-starts and even some random panic alarm issues until I did a couple..........?

 

I disconnected the ground cable from the battery a couple of days ago but haven't got back to it yet. I guess I could just reconnect and try driving the route again and see what happens (bringing it back home of course). But...is there an advantage to going any further with the reset/discharge and pulling the positive cable off and holding it to the negative cable (???).

 

Probably not, but you can use a short piece of wire or even your wrench to reach the pos terminal w/o disconnecting it.

 

Correct procedure:

1- disconnect negative cable at battery
2- turn ignition to ON position
3- hold end of negative battery cable to the still- connected POSITIVE terminal for at least 20 seconds
4- turn ignition back to OFF position
5- reconnect negative cable to battery
6- done, but you'll need to reprogram your windows


.

 

OK. And, that's safe...and better than just doing the negative disconnect?

 

According to WhiteXKR and other sources, this is the only way to actually reset the ECM. I've done it several times, it's safe.




.

 

Thanks. I'll do it before I drive her again.

 

Quick update: did the hard reset, took the kitty out for a drive and she did just fine, then started fine an hour later. So, I thought I'd take a chance and driver her to lunch with some friends about 15 miles away. Drove nicely, started fine and drove great on return trip. The reset seems to have worked but my door locks still go through several cycles when I open the driver door after stopping. I hope it's not the pass door latch system I already replaced a year or two ago.

BUT.....had one scary moment when I // parked at the restaurant. I was backing in and bumped up against a curb directly behind me. Not hard, just a bump. The whole car shut down. Engine stopped, steering wheel locked (full turn to left), transmission locked, etc. It took a few minutes of patient key off, then restart after several attempts. Was that some kind of security lockout???