Car died - no sparks - thoughts?

[spuggy]

Hi,

Apologies for the long post, but I'd appreciate any comments.

Today I changed the distributor cap, rotor, put new plug leads on. Car ran great (cleaned up the lumpy idle a treat).

I'm planning on getting an FR Wilk chip Real Soon Now, so I swapped in my spare, stock, DME from ebay as well to test it (I'm planning on keeping one unmolested). Car still ran great. New DME is the identical Bosch/Porsche part # as the original, BTW. Seemed clean and undamaged, hadn't been opened.

Drove the car home (5 miles). Ran great - noticed the low to mid-range was much improved too, much cleaner. Cursed myself for not doing the distributor before.

Drove the car out (10 miles, from cold). Ran great.

Drove the car home, (8 miles, from cold), stopped for latte supplies. Was running great.

Went to leave about 20 minutes later, car started perfectly normally, put it in gear, let clutch out, got 3 feet. Thought I'd stalled it at first. Odd.

Cranked it over 20-25 revs, rev counter moved, not a hint of firing. Realized it hadn't stalled.

Popped the hood, noticed faint odor of gas, re-seated all the new plug leads etc. - paying especial attention to the coil-distributor one. None of them seemed loose.

Cranked it, no fire.

Swapped in the brand new DME relay from the glovebox, cranked it. Still no fire. Gas odor now much more noticable under the hood, don't want to flood it.

Another once over on the leads, cranked it, still no fire.

Starting to suspect from the symptoms that the new rotor has fallen off, but don't have the stubby screwdriver or hex wrenches with me - and anyway, I distinctly recall blue-loctiting the lock screw into place and torquing it the approved amount (which was tighter than it was, and it hadn't come loose in the previous 12,000 miles).

Pushed the car back into the parking spot, dropped the hood, sat in the car.

Waited 3 minutes whilst considering the relative merits of AAA/hoofing it home with the groceries and hiking back with more tools, original DME, plug leads etc. tomorrow.

Cranked it one more time just for the hell of it.

It fired up entirely as normal, drove it home without incident. Ran fine, no missing or sputtering etc.

WTF???? I'm thinking I'd like to put back the original DME, but only because it's the only thing I can think of that was changed that could possibly exhibit these symptoms, and the cars never done anything like this before.

Anyone got any ideas? it was like someone hit a hidden kill switch...

Thanks in advance.

[nynor]

i had the same problem with a euro DME i purchased off of eBay. car would run fine then die. eventually, the DME would crap out more and more frequently until it quit altogether. i tried resoldering connections, did not work. i think it had finally burnt (or worn out) a chip or chips inside of it.

[spuggy]

Cool, so long as this is a real failure mode, I don't have a problem with putting the original DME back in.. Thanks for the reply!

[spuggy]

FR, both DMEs worked, both DME relays worked (the brand-new one from the glove box made no difference whatsoever).

The "new" DME is a suspect in a "whodunnit" scenario where I got nostart for 10 minutes in a parking lot after midnight for no apparent reason - with the car magically firing up just fine after I'd already given up prodding connectors and wiggling leads etc.

The "old" DME had never done that.

Although I replaced a fair amount of ignition components the same day, I did check starting the engine in-between, and drove ~20 miles without them missing a beat.

I drove the car to work this AM with the same components in it that wouldn't start last night - it seems fine.

I guess the question was really "can a DME fail on a warm-start like this and "heal" itself after it cools a little more", and someone else confirmed they'd had similar symptoms with a S/H DME.

[spuggy]

Well, hey, just in case someone else wonders about this - I left that "new" DME in the car.

Idle (especially when cold) got rougher and rougher. One morning it "sumbled" really badly and idle speed shot up to 1,500 RPM as it recovered, and about two minutes later, it stumbled badly again and stalled, first time ever.

Leaving work tonight, fired normally on two cylinders and then died completely. Tach needle bobbling about when cranking, but no fire. Checked HT and plug leads, nothing wrong, no difference.

Swapped back in the original DME and it started right up immediately, idled smoother, drove well..

Hmmm. Guess this means I have an emergency DME rather than a good spare...

[Mike Markota]

Did your car sputter and the tach jump around before it died?

[Eldorado]

he probably doesn't remember 2 years back

[SoCal Driver]

His last post was the first of this year.

[spuggy]

Hi,

my recollection from two years later was that is simply didn't start twice and I swapped it out - I was really surprised to notice my own post saying that it idled worse and worse over a period of time..

When it died the second time, it literally fired on two cylinders and then just cranked and cranked until I replaced it.

I'd had enough at that point. Never got a replacement or a refund of my $80 from the breakers I bought it from either, despite my shipping it back to them at their suggestion.

Think they were called Avenue Autoparts or somesuch. One to avoid...