Still No Spark

[burnt_toast]

Well at the very beginning when I got the car back from my father, the water pump had been leaking a long time, spraying back toward the alternator, and eventually the alternator let go too. So I got the car back running, but with the alternator light on. Like I said though, the car ran. I then changed the water pump, alternator, and timing belt. Perhaps I did not disconnect the battery when doing the alternator? It was over 2yrs ago so I dont remember. Still, wth the key OFF I dont know how ypu could fty an ECA by messing with an alternator.

I too believe that with no switching signal getting to the ICM and no pulsing signal getting to the injectors, the ECA is the likely culprit. Add to it the lack of a check engine light and Im very suspect. If it were fusible links or the main relay, I would expect to see more wrong. Plus he tests I did appear to confirm the links are good, right?

Getnpsi just loaned me a 1.6L ECA so I can substitute now. The main question now is, how do we know tyere is not a short or bad ground that will either damage this ECA or duplicate the problem due to its ground still being bad? Id hate to have to buy two ECA's.

Im not surprised at the ECA just going for no apparent reason. This JUST happened to my van when the engine bay became heat soaked. The CEL would not come on and I would get spark but no fuel until setting a fan in front of the computer fr 15min. After much troubleshooting I got a computer and it runs fine. Ive also had multiple CDI boxes go bad on 1980's motorcycles. True, the Festy computer is in the cabin and should be free from the environment, but the wizzardry can leak out of those magic boxes for no reason.

I share ypur opinon though that the home mechanic too often STARTS at the computer and works back. I understand we usually must test EVERY component associated with the computer and, finding them all good, condemn the computer. Thats why I havent given up. Thats also why I will never own modern cars or anything with a CAN-bus controller, making these types of checks impossible to do.

Anyway, can you think of any reason we should fear plugging a new ECA in for testing? Obviously I would disconnect the battery during the swap. Although my testing has been haphazard and confusing, I believe the ECA is the culprit.
Sorry forcthe spelling, im on my phone again and cant see what Im typing.
-toast

[burnt_toast]

Bad news. Swapped the ECA. Still no spark.
With access to the wires I pushed the logic probe through the insulation on the injector wires right at the ECA. The GRN/YEL and GRN/BLK showed no light in any position. The BLU/ORN SPOUT wire just confused me though. On the ECA it looks like it's actually pulsing. It's really hard to tell though. At the ICM is does NOT appear to be pulsing. The schematic shows that wire as a straight shot from the ECA to the ICM. How in the hell could that happen without a broken wire? And how the hell is there an injector pulse problem with a new ECA? The plot really just thickened.... like concrete.

Also, there is still no CEL.


-toast

[burnt_toast]

Riddle me this:

WTF are these two wires doing hanging out next to the key switch?!!

http://johnnykillmore.smugmug.com/Ot...17.23.29-L.jpg

The green one I'm guessing is to the horn since holding the logic probe to it creates an eerie moan from the front of the car after a few seconds (and the horn wire on the schematic is green).

The RED/YEL I am not finding. Unfortunately when I tried to move it away from the key switch a fat blue spark came off of it which means I'm slightly more than just curious about what it is. I started thinking maybe something was wrong in the key and the computer was not being given power, so I pulled the cover off to find these two wires staring me in the face. Both have dabs of solder that are flat like they were soldered to the side of something. I can't find the red/yel's origin though...
-toast

[purg3d]

I've seen those wires cut, but never with solder. Ran fine without. Would a faulty oil pressure switch cause a no spark situation? I'm sure you've checked and rechecked connections. Sorry to read about your trouble, but I'm confident you can figure it out.

[burnt_toast]

Looking at the schematic I found a Red/Yel wire that goes from the door buzzer to the ignition reminder switch so I suppose it could be that. I know the buzzer doesn't work with the key in and the door open. Damn, I was hoping I was on to something.

As for the oil pressure switch, the wire just goes straight from the switch to the dashboard so it has nothing to do with the fuel injection system or ignition system.

-toast

[tooldude]

Holy Festvolts!! Take 2 aspirin and sneak up on that car from behind. Ignition on, turn on everything one at a time and find out everything that isn't working. My first thought is that there are no terminals on the end of those wires, so they were soldered onto a switch. They're short so it must be close, maybe you can see what they reach to. Working only from the schematic, I see a solid green wire runs from the horn switch to the horn relay and a R/Y wire runs from the headlamp switch to the parking lamp relay. Might be a blown fuse now.

[burnt_toast]

In any event it doesnt look like it has anyrhing to do with the missing spark and injection pulse. Im out of ideas now. Im scratching my head and moving back to square 1. I dont know what it could possibly be anymore

[tooldude]

Well, after a little research, according to Mr.Probst, engineer, MECS cold start strategy is similar to EEC (except 1.6L & 2.2L non-turbo) for fuel & spark timing. Bottom line, this might mean it's normal for the ECA to have no SPOUT signal during cranking. If that is true you're left with the problem that your injectors are not being grounded by the ECA during cranking. That brings up the premise again that the ECA grounding could be bad. The EVTM shows ECA terminal 2B grounding at G102 and terminals 2A,2C,2D,&2J route through 4 splices in the wiring harness, then ground at G103. G103 is listed at "LR side of engine compartment, at frame". G102 is listed at "engine compartment, near coolant temp. sensor". Also, when you changed the alternator did you remove a ground strap?-those grounds need checking too. What is called rear of the engine compartment looks like it's more like off-center than in the back. (There is also a ground on each fender well, more forward to check, G100 & G101). You may need to check continuity & resistance through the ECA connectors to ground. Hopefully, there is no problem with a splice point in the harness.

[burnt_toast]

How could there be no SPOUT signal during cranking? That wire goes directly to the ICM. How can the ICM create a spark if it's not being given a signal from the ECA to do so?

Grounds are still a fine possibility though so I'll have a look around based on your information. Hellish problems like this are very often a grounding problem in vehicles of this era, so just based on statistics it's worth a shot. I did not remove the alternator ground strap during R/R. I did remove it in the troubleshooting process and cleaned all mating surfaces before reinstalling though.
-toast

[Kbaker2012]

Hey Burnt Toast. . . Have you tried another distributor. The crankshaft sensor is located inside the distributor and if it is bad it WILL NOT fire. The only way to replace it is to get another distributor as a aftermarket Crankshaft is not offered. Hit me back with what you find out.

[tooldude]

How do you get those nifty little quote boxes for just the part you want to respond to? OK, I was saying,"IF", conditional if MECS-I acts like other EEC. From MR.Probst's book, Ford Fuel Injection: ENGINE CONTROL FUNDAMENTALS--CRANKING vs STARTING ;"In defining strategies, Ford makes a distinction between cranking and starting. Cranking needs it's own strategy because the engine-control computer cannot depend on the usual signals from the sensors to compute fuel injection, spark timing, or idle rpm.....The most important considerations:*Programmed rich mixture, with fixed air-fuel ratios:12:1 for a warm crank, 2:1 for a cold crank.*Fixed spark timing..... Then>MECS-II--ENGINE CRANK SUMMARY;*"Fuel injection pulse times from lookup tables.....",*"Spark timing directly from PIP, 10 [degrees] BTDC. *No SPOUT." >now quoting me,"this MIGHT MEAN it's normal for the ECA to have no SPOUT signal during cranking." So to not chase ghosts, I'm thinking, deal with the injector grounding problem because, solved, that will probably be the end of it. How could there be no SPOUT during cranking?--by programming the computer to do that.

[tooldude]

Hey Burnt Toast. . . Have you tried another distributor. The crankshaft sensor is located inside the distributor and if it is bad it WILL NOT fire. The only way to replace it is to get another distributor as a aftermarket Crankshaft is not offered. Hit me back with what you find out.

He did all that. This is a long thread, you have to go back and read through it to know what's going on.

[burnt_toast]

Hey you found the quote box!!! Handy feature, eh?

Yes, new distributor. We are about to run into a long break. I have a race in Utah and must leave Thursday morning, not to return until kicking some ass at high speed. Wed is loading and prepping the van/trailer/bike for the haul out there. I'll poke around in a minute (now that it's the hottest part of the day) but I can't make any concerted effort to check the grounds without a big block of time.

I get the diff between cranking and starting, but I don't get why the ECA would not think to start the engine if it's receiving a VAF and CKP signal. What other events would it require to suddenly go, "hey the engine is trying to start, lemmie do all those things I do." ????
-toast

PS Yeah I don't get the quote boxes to take just the part I want btw... I just use the quote shortcut in the toolbar, then cut/paste what I want (though it appears you've figured it out just fine).

[burnt_toast]

http://johnnykillmore.smugmug.com/Other/My-Smug-Mug/i-XVxhgzt/0/S/2013-08-27%2014.54.30-S.jpg

^^^^^^^^^^^^^^ right there ^^^^^^^^^^^^^^^^

[FestYboy]

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