Z31 HELP!!!

[kasilvia]

Okay, so I have an 87 N/A Z. This car has been a great DD while my 240 is down for "overhaul", that is up until now. I no longer trust this car any further than I could throw it. I am hoping that someone has experienced what I am going through with this car before, and could nudge me in the right direction. If you think you can help, please read on, otherwise thanks for reading this far.Synopsis: Car starts and drives normal without any warning of what is about to come. Drives fine for a roughly 25 min span of time. Some of that time at interstate speed some sitting in traffic, and some just parked running. This is my typical commute home from work, except this time, while sitting on a slight incline at a stop light it happened. It started with a slight raise in idle, followed by the inability of the car to maintain idle. With the gas pedal fully depressed, the engine sounded like it was bouncing off of a 2300rpm launch controler, wild exhaust explosions and a tachometer that was jumping around feverishly between 100rpm and 4000rpm. I try to lift the clutch to ease the car forward in hopes of limping my embarassing pyrotechnics display on wheels home, but the car has absolutely no power to do so. It will give up a good fight with the pedal on the floor, popping and stumbling while sulphurus smoke pours out of the exhaust, and then begins to smell of burnt metal. After maybe 40 seconds of fighting, the engine gives way and dies. I attempt to start it back, hoping it was just a freak occurance, it just spins and spins. No start. I wait as traffic piles behind me, still no start. Twenty five minutes later, a tow truck arrives, just for grins, still no start. Twenty more minutes and $85 dollars later, car is coming off the rollback. I dont know if by habit or what, I hop in, twist the key over, and bam, she fires like off the showroom floor, then quickly thereafter dies, only much less dramtically than before. One more crank to assure me that she deserved to be trailered to my shop, only to be smacked in the face when she starts and drives into my shop. I can no longer diagnose my problem because it now has run for over thirty minutes while I waited for it to die again. This is the third time in roughly 12000 miles (over two years time span) that it has given me the dramatic death and then refused to start, only to start after roughly 1 hour of sitting. Any ideas, or testing data for components such as the distributor (more specifically the crank angle sensor), MAF, or any other part that you recommend I look into. I am wracking myself trying to figure this one out, and it never dies on me when somebody is with me to help diagnose when it is dead (i.e. to turn the engine over to check for spark) so I have no useful data as to what system the problem lies in. Thanks for reading my book,Luke

[evilhomer]

I think you want one forum over:

Classic Z Forum zeroforum?id=194A forum for the classic Z-cars - 240Z, 260Z, 280ZX, pre-'90 300ZX and Fairlady.

[kasilvia]

Ouch, reading comprehension owned me.... Is there any way a MOd might be able to help me move this thread?? I know it is a very long post, and I am tired of typing. Any help please?

[evildky]

moved it, it's tough to diagnose intermitant problems, but a simple test, keep a can of starting fluid in your car, when it dies give it a shot in the intake see if it fires right up then dies again or if it still won't start, if the starting fluid doesn't do anything then we can rule otu fuel issues, and honestly I'd tend to suspect the ignition, the ignitor looks like a quarter welded to a bracket mounted to the inside of the fender behind the drivers headlight could be failing intermitantly, best suggestion replace with one from a junkyard and see if fails again, and my last idea would be the distributor, they are optical and I know in the L6 they can fail intermitatntly and wierd, might try locating one to swap in if the others tests don't help

also was the injector recall done on your car? you can call your local nissan dealer with the vin number to find out, it's good for some free parts if it hasn't been done yet

[AZ-ZBum]

Unplug the AFM and see if it idles/starts better. It won't rev over about 2300 rpms, but if it runs fine to that point, then that's your problem.

[kasilvia]

Thanks for the advice, and I will definitely look into that injector recall. I will pick up a can of starting fluid, and hopefully wont have to use it! I have suspected the distributor, but being VERY intermittent, I guess having all the tools and a remote starter in the back to diagnose it may be the ticket. I hope this works out, because my father and I use this car as our back-up car when our toys are down (he has a 3000gt vr4, enough said). I will post what I find when it all washes out.

[kasilvia]

It usually runs perfectly fine, only very rarely does it ever do this. I will try unplugging it if starter fluid wont do it. Thanks for the input, any suggestions at this point will help point me towards the right answer.

[AZ-ZBum]

Don't use starting fluid. That's for carbed cars.

[evildky]

nothing wrong with starting fluid in a non running injected car, just a simeple shot to see if the car will fire at all, no fire = spark problem, a lot of people will swear startng fluid or race gas will ruin all kinds of sensors but from my experience it won't, maybe if you do enough it can but if your using your head at all it should not be a problem

sorry AZ, I respect your opinions and view you as the Z31 authority but moderate use as a diagnostic tool should cause no ill efects