Stuck in Seville Ohio

Thanks again to all. I am sitting in my office now. The damn thing ran like a train all the way home. Lots of 5000 RPM in top gear.

Cool story. Seville is about five miles from where I grew up (Wadsworth) but moved away from in 1997. I had a hunch Pat G would enter the story. Not disappointed at all. 

In reply to TurnerX19 :

Awesome!!!

Still headed home here. Was checking every 5 minutes for updates while making the exhaust for Colin.  And wouldn't you know it, the check engine light came on in the Volvo, and the heat is ice cold all of a sudden.  Maybe the Volvo transmuted the Fiat's problems 

In reply to Pete. (l33t FS) :

you got them too close together 

Glad you're home, Bill!

Bill I'm happy you made it home and also BIG thanks to everyone who jumped in to help!

Not super fun to sell a car that dies the next day, but hopefully this is only a hiccup.

Glad you made it. Sorry I didn't see this sooner, would have been happy to lend a hand and meet you.

In reply to Robbie (Forum Supporter) :

Is not like you sold him a 10 year old Camry.  A long adventure in an old Fiat should be exactly this...an adventure! 

Also, getting to interact with Robbie, Patrick, and Pete all in one trip is quite the trifecta of GRM-greatness. 

I wish there was a grm presence like this on the pacific side of the country

Note to self- 

Be sure to ONLY Break down in Northern Ohio, forever. 

jfryjfry said:

I wish there was a grm presence like this on the pacific side of the country

You're there, that's one.

In reply to 759NRNG :

https://grassrootsmotorsports.com/forum/grm/grm-on-the-road-assist-list/90668/page1/

Pete. (l33t FS) said:

In reply to Patrick :

I would have been happier if the last time it quit, I had been watching the spark tester.

The only real clue is that it would be flooded when trying to restart.  Fuel pump stayed running when it would stall, it is very audible when your head is behind the passenger seat.

But then it stopped not running, which is the opposite of what should be annoying.

I've been thinking about this a lot and I now wonder if it isn't the fuel at all, but rather spark. 

That Haltech unit is (I believe) fuel only, and spark is still managed through the fiat distributor and the ignition module. I'd think you'd have at least a bit of run on or sputter or something if the fuel cut out or suddenly went mega rich but the spark was still working. 

I looked at some fiat wiring stuff today (for other reasons, but this caught my eye), and, sure enough, the 'switched power' to the ignition control unit and the coil is on a circuit that is sketchy at best. Battery power goes from battery, through a distribution connector, through the ignition switch, to a 'bus' wire, that is probably 15 feet long. That bus wire connects to the following: coil field light, headlight motor control relay, power window relay, coolant fan relay, the radio (which there is none in this case), the ignition module, and the coil (through a resistor and also to ground with a capacitor). Oh, the bus wire changes colors at least twice, and is only 16 AWG. 

My point is, I could easily see low battery voltage due to cold, higher loads, etc being exacerbated through a series of not-quite perfect connections and that adding up to not-so-great voltage at the switched side of the ignition module. If the system is just right on the edge, then any sudden load on the battery could cause a system voltage drop just enough to make the ignition module 'turn off'. 

https://xwebforums.com/wiki/images/c/c7/ElectricalDiagnosticManual.pdf

Anyway, maybe a good check would be to check the difference between the battery voltage and the switched power input at the ignition module with the key on engine off, but also with key on engine running. I think ruling out a voltage drop between the ignition switch and the ignition module would be a good thing. But could also be other ignition related stuff causing low voltage on that bus. Like the capacitor by the coil not working well in the cold. 

Also, did you guys have it on a battery charger while you were troubleshooting? Maybe the issue went away because the battery got back above a certain voltage. 

In reply to Robbie (Forum Supporter) :

When it would cut out, the ignition coil was still getting 10v through the 1.25 ohm ballast resistor. 14v+ supplied to the ballast.  Negative side was still getting switched, tach was twitching.  We went to go get an inline spark tester and it only stalled one more time after that.  It was a good 15 degrees warmer since 8:30 and the engine had built itself up to operating temp.

That cap had me suspicious but I never saw the coil get dragged to ground or kept at voltage.  Did clean up all spade terminals I could find while I was in there.  Did it help, did it do nothing?  It made me feel better, at least.

Charging system unlikely, had a solid 14.38v with the engine running.

In reply to Pete. (l33t FS) :

i'm going to keep telling myself that it was the tps wire rubbing on the bolt, so i can feel good about it

In reply to Patrick :

I checked it versus ground, and either the insulation was still intact, or it was a ground wire so it didn't matter anyway.

I mean, one COULD blame it on being a Ford part   I like Fords but my like of Fords ends around the time they went to electronic ignition.  This is merely as a way to define an era, mind you.  I have Many Bad Words to say about Ford points distributors.

The more interesting thing, beyond how it would be flooded when trying to restart, is that it seemed to run better when I wiggled the MAP connector.

The MAP sensor had the awful GM green connector that they apparently made out of rapid biodegradable compressed Cheez-Wiz or something.  There was barely any connector left, it was mostly just three Weatherpak terminals loosely held in formation by a green framework.

I have done many, many intake gaskets on 3100s and 3400s.  GM had Metri-pak connectors everywhere except that legacy MAP sensor, with the green connector that broke if you looked at it too hard.  It was SOP in the shop to never actually unplug the MAP, just remove it from the manifold and let it dangle from the wiring harness.  The connector would always break if you touched it.  Even more brittle than Toyota ignition coil connectors.

Started yesterday and today no problems. Temp over 45* both days. Haltec software is free for this unit. I intend to acquire. I think it over fuels below a certain temp and will try to prove it.

Well at least I am glad that I sorta followed a similar line of thinking to what you guys clearly already ruled out!

In reply to Robbie (Forum Supporter) :

For sure, I have never seen an overfuel issue cause an immediate shutoff like that.  But it seemed to have spark right up to the moment it stopped turning.  What else is there?  Ignition timing going to a point that the rotor phasing sends it to the wrong cylinder?  Most engines stop running when ignition timing goes 180 degrees off, but they usually backfire or spit up the intake when they do that.

I recall something about a variable rev limit based on coolant temp, maybe related?  Or a big fat load of who knows.  I have never tuned a Haltech so I don't know what the different tables look like or what happens if you go off scale.

Sorry but every time I see this thread pop back up to the top I can't help but think "oh lord, I'm stuck in Lodi again."

Thanks creedence. 

In reply to dculberson :

I put that song on every time I drive past Lodi on I71