US /vs/ EU ignitor module, HELP PLEASE?

[Red]

Ivan,thank you for thinking outside of the box. But since the engine is running spot on when it is running, and the "no start while hot" only applies to a "cold" engine (i.e. it is hot out, but the engine hasn't been running, isn't being restarted)...I don't think it would be timing.

I'd be more afraid of messing with the timing and creating more layers in the problem. Especially, as I'm far from home and my timing light doesn't travel with me.<G>

On the bright side, perhaps I've eliminated the ECU as a problem...perhaps not...I'm wondering if there's some clever way to fake the pulses from the distributor to see if that's the issue. But meanwhile, I'll freeze the ignitor. Not because I think the ignitor is bad (it gets way hotter while the engine is running, right?!) but because it is a test that I can do, with what I have.

I can't help thinking, it really SHOULD be an ECU problem, or the startup signals from the distributor, based on when and how it misbehaves. But there are no real gurus for these ignition systems left. All the "diagnostics" in the US now consisst of "plug in the OBDC port reader" and oh, DUH? Of course we can't do that for a 1985.<G>

I hate to say, I can swap out the distributor, ECU, and ignitor all for less than "gee, it might take two days of diagnostics". Must remember not to kick car...will only hurt foot.<G>

[Ivan141]

Have you run a diagnostics check on the ECU whilst the problem was occurring?
Just trying to cover the basics here. If it's an electrical gremlin, it might show up on the ECU. Have you pulled a spark-plug to see if the engine was flooded after multiple start-up attempts or rather the opposite?
Another thing worth fiddling with is the AFM, you can try restricting the inlet with your hands whilst cranking and see if it makes a difference in the sound of the engine. Have managed to start a reluctant car with a faulty AFM sensor once that way.

As always with starting problems you need to check the 3 basics, air, fuel and spark. Fuel is rarely a problem, can easily be checked as well (maybe not very safely, but what the hey). Spark is also relatively easy to check, air and mixture are a bit more fiddly. I get the feeling you're over-analyzing the ignition bit at the moment, which may blind you of other possible causes.

[Red]

"Have you run a diagnostics check on the ECU whilst the problem was occurring? " Diagnostics check how? On an 85 ECU, there's only ten codes, no diagnostic port, no OBDC. So...diagnostics how??

I'm working solo so the simple things like checking spark aren't always simple, but since it DOES fire up on the starter, not just turn over but stumble and fire up, there's some spark going on. Just not staying on.

Fuel is on my list to check, but I'm dead certain, like you say, that I'm overthinking this one. I just KNOW it is going to be "SOMETHING SIMPLE, STUPID" and a Homer Simpson "D'Oh!" moment if I ever do pin it down.

In the meantime, the car outweighs me. This is not a fair fight.

Either pulling a plug, or disconnecting a fuel line...yes, checking that the fuel pump and regulator are doing more than making a 'whirr' noise is on the short list to come. I just (over)think it can't be a fuel problem, since the car runs without stumbling even at 80mph for hours on end, and that means it sure is getting fuel from SOMEplace. Lots of fuel, without problems.

Which comes back to a starting-when-ambient-hot problem, which comes back to ignition, no? And since it starts just fine when the engine bay is at operating temperatures (way higher than ambient) that means it "must" be something that's not in the engine bay. Which comes back to ECU or COR (bypassed & tested AFM & COR & EFI relays) or fuel pump, but since the fuel pump normally sits in "hot" fuel returned from the engine when the car has been running all day...it comes back to "needs exorcism", right?

Come on, Ivan. I'll sponsor you for an H1B visa to work in the States as a "necessary skill that can't be found here".

Damned unreliable riceburner, only 26 years old and it won't start! <vbg>

[Ivan141]

I'm no guru, just a methodical bodger

You say it does turn over but dies again... that to me points to another possibility: circuit opening relay going bad.
The fuel pump is powered through this relay under operating conditions. EXCEPT when starting, in which case it gets direct current through the ignition key.
Relays are also known to exhibit warm weather problems in cars, I found a bunch of mentions of similar issues in honda civics.

Run a direct 12V feed to your pump to rule this out, or attach a light to the existing feed and check if the light stays lit after starting.

I'm not saying this is your problem, but it pays to know what is NOT the problem, so check out everything you possibly can.

BTW, Thanks for the offer but I'm quite happy over here on the old continent :wink:

PS: are you the Red from club4ag that had his car stolen a few years ago?

[Red]

"PS: are you the Red from club4ag that had his car stolen a few years ago?" Yes indeed. You've got quite some memory, the last theft/attempt was a true theft around 1995. The last attempt was some years later, they literally BENT OUT THE FREAKING WINDOW FRAME because I had the door locks shaved so they couldn't be punched.

"You say it does turn over but dies again... that to me points to another possibility: circuit opening relay going bad. "
Nah. Been there, ran a bypass jumper (pins 1/2) to take the COR out of the circuit completely. And then used a test light on the fuel pump power leads, so I could see from the driver's seat that the fuel pump was getting power, during crank and "on".

I only wish it was the COR! I'd actually removed it, opened it up, confirmed both circuits engage with just a 9v transistor battery (which is a good way to test 12v relays, if they engage at 9, they'll engage firmly at 12) AND I checked the contact arms visually (no pitting or anything) and with a multimeter to make sure. Then rechecked again after re-assembling it, because I've seen Bosch relays where parts are fixed through the case, and shift when the case is closed.

"Run a direct 12V feed to your pump to rule this out, or attach a light to the existing feed and check if the light stays lit after starting. " Done and done as above.

"it pays to know what is NOT the problem, so check out everything you possibly can. " ABSOLUTELY! I assume you've read Sherlock Holmes and know the bit about "once you've eliminated all the...whatever remains, no matter how improbable, must be the problem" or words to that extent?

Or as it is sometimes called, "the relentless applicaiton of logic". There's only so many parts in this system, and one of them is hiding under obscurity. I'm almost mad enough to build a pulse generator out of a 555 timer, and feed the car a fake distributor signal in order to eliminate THAT as a possibility. If I had access to a scope, or a tech with a scope...But as they explained to me, no one has scopes anymore, the OBDC port is all they need. (HA)

Even then...logic says it is nothing under the hood, or else it wouldn't do highway restarts, when the whole engine bay is way much hotter. THAT has to point to something, I just don't know what. Fuel pump? Fuel tank vent system and charcoal filter valving? Some other "startup only" circuit?

There's got to be something that hits this specific problem.

Adding insult to injury, the guys on Top Gear (UK) had the nerve to test a Nissan GTR in that gorgeous blue metallic color. If I had a spare $85k I'd be ready to dump my old ride instead of fixing it.

I couldn't make the first payment on a GTR, but that's OK, given US speed limits I'd be safely in jail and it would be in an impound lot before the first month was up anyway.<VBG>