Still No Spark

[burnt_toast]

Continued from here: http://www.fordfestiva.com/forums/sh...-spark-Somehow

Hello all,

I've left my Festiva gathering cobwebs in the driveway for way too long now. I've done a lot to try and fix this problem, so there is a lot of info to pass on here before I can ask for help. Lemmie give the basics:

1992 Festiva 1.3L 5-spd mechanically stock. I gave it to my dad who basically tried to kill it for two years with a lack of maintenance and general neglect. So, when I got it back I did the following things. Mind you, the car ran fine before I did the work. I replaced:

* Timing belt
* Water pump
* Alternator

After that I went to fire the thing up and it would crank but not start. I eventually determined there was no spark or some reason. I did a lot of testing and replacing/swapping. Here is what I did. I will try to explain the tests I did instead of "I found part X was bad" in case I did a test wrong or missed a test:

* The coil was getting 12V to it but nothing was coming out. From the bone yard I got a coil, the ignition trigger, and whatever the hell that little heat sink is (all the parts on the strut tower with the coil).

* I replaced each item one at a time but got o spark still. I purchased a new coil and it still did not work.

* I pulled the distributor cap and verified is was turning, then checked the 3-wires for the hall-effect pick up (cam position sensor).

* I have 12V on the constant wire but no pulsing on the trigger wire, checked with an oscilloscope (flat line). The ground wire has continuity to ground (valve cover).

* All the fuses are good: not blown, corrosion free, no loose blades.

*We check the Hall-effect pick up for corrosion but it looks mint inside, and it's not removable, so I bite the bullet and get a new distributor.

* There is still no spark. 12V constant wire is good, the ground is good. I don't have access to the oscilloscope or an analog multimeter currently, so I tried using a test light to verify the trigger wire and got nothing.

*** It just dawned on me: the check engine light (CEL) does not work. I tried to jump the wires to see if there were any codes stored, but the light does not come on. Never. The manual says it should come on when the key is in the "ON" position before cranking.

MY THOUGHTS:

Well, my thoughts are a string of cuss words, really. Other than that, perhaps it's time to get a new ECU? Perhaps when I changed the alternator I didn't disconnect the battery and arced something? I dunno how that would get to the ECU with the key off, but I'm at a loss for easy answers. The service manual shows the pick-up in the distributor is the crank and cam sensor, so I can't think of another sensor. The ECU should be getting a signal from the pick-up and telling the ignition system to get to work.

QUESTIONS:

* wtf?!!

* Other than that, does this model have an auto shutdown relay perhaps? Or some other relay that would stop the ignition system from activating? All the fuses are good.

* I assume there is no test for the ECU? As mentioned above, the CEL does not work. I'm thinking I need to pull the dash apart and verify the bulb is good. I just had a starting problem with my van that turned out to be the ECU, and that problem was the same... or at least that part of it was the same (the CEL).


So I know that's a ton of info, but it's better than having it strewn out over the next 10 posts as people ask me. I'm really out of ideas. Not having a job anymore means I can't throw parts at it like I had been in the past. The car needs back on the road; it actually gets better mileage than my motorcycle.

Thanks for any help,
-toast

[crazyrog17]

You may have, but I think we still need to rule out fuses. Have you checked the fusible links on the driver's side shock tower?

I don't know if the ECU and coil are on separate circuits but I'd hope so.. Check the fuses in the left knee dash too.

One other thing.. is the black ground cable bolted in place between the head and passenger's side shock tower? Something that could be overlooked after a tb/wp service.

[FestYboy]

is there injector pulse? also i would stop ruminating on the coil: if it's close to spec and it's got 12v, then focus on the ground side of that circuit, not the component itself. it IS possible that you picked up a bad ignition module (small black box that sits on the tower bracket and has 3wires to it). that unit is the ground control for the coil. if the coil never sees ground or always sees ground, it's that units fault.

[burnt_toast]

Oh yes, Im well past the coil at this point. Not sure how to check the coil for open/ground without an analog multimeter, though I recall doing some checks with my father and the oscilliscope on the coil, so maybe we already checked that?

Fusible links? I hate those things. No i did not check them; I did not know they were there. I will have a look.

I checked the fuses in the dash already, even swapped it with another fuse of same rating just in case there was corrosion in the blade under the plastic (had that once before).

The ground cable is there yes. I did not have to remove it. Its dirty as all hell though so I will
remove it and clean it while Im in there today looking at the fusible links.

Ok, off I go. Will report back.

[burnt_toast]

Oh I forgot the injection pulse. I never actually checked it but there is a smell of gas from the exhaust after repeated attempts so I just assumed the fuel side was alright.
Typing this on my phone makes it hard to remain coherent; the damn thing keeps re-centering istelf on a part of the text Im not typing, so I have to type blind while remembering what I want to say. Lost the internet this morning though.
-toast

[FestYboy]

ok i'll give you this hint: if you have power to the coil, injecors, and dash, the links are in good condition.

[burnt_toast]

Yeah the links were corroded but certainly okay (continuity). I checked the wire from the coil to the distributor, 800ohms. I checked the #1 plig wire since it was closest, 850ohms. Im back to the computer. I just tried pulling the dash because I want to verify the CEL is not burned out. He bastard will not let go. I can only remove it 2-3inches before the wires pull tight. How in the hell did they get it in if the wires are that short?!! Grr.

Going off of memory I dont remember the CEL coming on when the car ran. I remember trying to get the thing to come on years ago, but I really don't remember it that clearly.

Is there a way to verify the CEL works without taking a skill saw to the dashboard?

[Zanzer]

Unplug injector #1, set your meter for VDC, plug the probes into the injector plug from the harness, have someone spin the motor over and look to see if it has an injector pulse. I know you said you smelled gas but this will actually give you a "pass/fail" and if nothing else it solidly eliminates a variable.

[Chobobulous]

If you disconnect the speedo cable from the trans and push it up into the cabin a little it should give you more than enough room to play back there. Be careful not to break the plastic pins as you are disconnecting them from the gauge cluster.

[burnt_toast]

Sweet! It was the speedo cable holding it in. Well the bulb for the CEL is good; its not being lit by the ECU when the key is ON. I dont have anyone available to turn the car over for me, so the best I could do to test injector pulse was to put safety wire into theconnector, then wrap the other ends to the test leads, then put the multimeter on the windshield... then get blasted in the face by ancient shit-water when I flipped the key on because I was accidentay holding the windshield washer on as i reached through. I guess that last part isn't relevant, but I had to share is with someone...my eyes still burn.

So anyway, no response from the multimeter when cranking. Assuming my leads were making good contact, no injector pulse. For good measure I popped the fuel cap and put a stethoscope to the fill nozzle and cycled the key on. I heard no sound of the fuel pump cycling, which I assume would be loud enough to hear even without a stethoscope.

So I am starting to think I have no fuel, no spark, and no CEL, which all spell "ECU" to me. I just came off my '95 Dodge van having a no-start when hot. Spark but no fuel. When it did that I noticed there was no CEL or airbag light coming on either. Turned out to be the ECU. Having just come from that problem, I am now highly suspicious of the ECU when I get no CEL.

Anyone with other ideas? Im going to head over to ebay and part finder and see what is available.
-toast

[FestYboy]

you will NOT hear the pump unless you force it to run (jump test connector or move the flapper door in the VAF). the injector pulse is typicaly too fast for a DVOM to see it, thats why Noid lights are used.

backprobe the power (12v) pins of the ECU and also make sure the injector harness has a constant 12v with the key on.

[Chobobulous]

Isn't there a wire you can ground that will make the fuel pump run. Its in the area of the self diagnostic wire. I think.

[burnt_toast]

The pump should come on when cranking though. This car is small enough for me to put the stethoscope to the filler tube while cranking. I heard nothing. I'll check for a constant 12v on the injectors though. I expected the multimeter would at least start jumping around and giving unstable readings if a pulse was going through. Unfortunately I do not have a noid light, just a standard test light and digital multimeter.
-toast

[burnt_toast]

Oh, and the ECU. I have no idea which wires are the 12V for the EFI... the manual does not seem to have these checks (Haynes). I also am having zero luck disconnecting the ECM wiring. They are welded in there.
-toast

[Chobobulous]

The pump would come on when the vaf opens a little due to the vacuum draw on the engine. Maybe the wire over there is unplugged.