I drove the Z earlier today with no problems. Then I started it up about an hour ago and this is happening:

1) The tachometer needle is bouncing up an down randomly. Just the needle itself, the engine speed remains as it always would.
2) My healdights are flashing on and off, also randomly. They'll stay on for a while, then go off, or dim, or switch between high and low beams. This is happening with or without them actually being switched on! This is totally dangerous at night!
3) My speedometer is motionless, stuck at zero. The same for the digital speedometer, it stays at zero.
4) The DSC, Slip, and ABS lights are constantly on, with the TPS light comming on and off intermittently.
5) My turn signals will work properly, then randomly slow down or just stay on at all times, WTF?!?
6) My horn does not beep when I lock my car with the key fob. But the horn does work from the steering wheel as normal.

I disconnected the battery for some 30 seconds but this did nothing, the problems remain. What I did find is that these problems only occur with the engine on. If I move the ignition to the "on" position but dont actually start the engine, everything works as it should. But as soon as the engine is started, all of these problems occur. All of the mechanicals (engine, clutch, transmission) feel fine with no noticeable issues.

What the heck could be happening to this car??? Any help or info is greatly appreciated. Thanks in advance


djlast

 

is the car used? has ANY work been done to it?

 

Sorry, I guess I should have said this on the first post. It's a 2003 Performance Z with a 6 speed tranny. I've had it for 3 and a half years now and I got it new from the dealer. It's never given me any problems aside from the common ones (tire feathering, some gear grinding) and never anything like this. All of the regular maintenance has been performed.

 

Now this morning the car won't start at all. The starter turns but the engine won't start. This sucks!

 

Have you checked the charge/life on your battery?

 

Sounds like the voltage regulator in your alternator is gone. If you have a voltmeter, check your voltage drop across your terminals with both the car on and off.

Off you should read 12 V

On you should read about 14.1 V (+/- a volt is fine)

If your voltage fluctuates in the on position (should remain steady), you most likely will need a new or rebuilt alternator. You can also go to Autozone or pepboys and have them measure the voltage drop if you don't have a meter yourself.

 

Thanks for the info. Well, this morning the car wouldn't start so I hoped maybe I could get it started with a the classic drop-the-clutch-while-rolling start that used to work on my old MX-6 (I figured I'd try it since I'd have to call for a tow either way). Well, it didn't start, the tires just locked up in first and, in second, it would just come to a halt. So since I took a chance and got stuck on the road, I had to call for the tow and had it taken to the dealer.

I hadn't seen the post about the battery level or the alternator until I got back home just a few minutes ago so I didn't get to try that out. How much does something like a new alternator installation cost? I'm sure it's a ridiculous number. For now it's at the dealership, hopefully it won't be as bad as it seems. But really, what the hell?? I've never seen a car act so weird, turning it's own lights on and off randomly, needles jumping around like that. I hope this is not a common thing among Z's.

Well anyway, I'll let you know what happens. Thanks again for the info.

 

A new alternator should run about $150-$200. If you take it to good car electrical shop, they might be able to rebuild it for less than $100. I haven't even bothered to look at where the alternator is on the VQ yet, but for every car, the labor charges will be different.

I used to have a Chevy Corisca sedan...engine was designed with the mechanic in mind and the alternator sat at the top of the bay with easy access to all the mounting points and the tensioner pully. It took me 20 minutes to swap in a new one.

I did the same job on my Dodge Stealth, and the alternator was put in the worst possible place, right above the frame...That one took me about 3 hours and prying the engine over 1/2" to get done.

If you have a shop manual, now would be the time to look at expected times.

 

I'm sorry I didn't post this up yet but I've been away for a while.

This is what the dealer told me (which most likely is BS but at this point my hands were tied):

The computer that controls the key-ignition security system (I believe he called it NATS) was dead from some sort of short-circuit. Because this computer is located inside the ABS control module, the entire unit needed to be replaced. Once they replaced this unit, they were able to trace the problem to a battery-acid leak that had devleoped over time and happened to leak on the IPDM harness & module which caused the short on the EBCM. This IPDM was cleaned and repaired and this brought everything back to normal operation.

All I know is I'm out $2300 on some bullisht electrical problem that I'm sure is a factory defect but because I just went over my warranty, I got stuck with the ridiculous bill.

This will be the last Nissan I ever own!! POS!! (But yesterday a fine honey was all checkin it out, so at least it has that, but I'm still mad at it!)

djlast