Today I had the auto parts store test the ignitor with their testing machine. Tested fine. I haven't noticed any loose/dirty/corroded connections. With the rotor cracked as I posted pictures, could that possibly throw a code 15 with ignition just turned to on?

 

Code 15 is an electrical fault (short or open) in the ignition output signal circuit.

Since ignitor checked OK, this leave two possibities; open/short in Yel/Grn wire between ECM and ignitor, or ECM fault.

Yel/Grn wire can be checked by disconnecting at ECM and shorting connector pin for yel/grn to ground at distributor/harness connector. If check at ECM connector shows open, the yel/grn wire has an open circuit that must be found/repaired. If it shows shorted, remove ground short at distributor and check again for open circuit on yel/grn. If now open, the wire is good. If it shows shorted, there is a short to ground that must be found/repaired.

If yel/grn wire checks OK, then time to locate a used ECM (ebay, car-part.com) and swap ECM.

good luck

 

Texas, thanks for the description on how to check for open/short in the yel/grn wire. Looks rather complicated to me, and when I do that I'd probably need some more descriptive step-by-step details on the process, which I will ask for here when/if I get to that point. I really don't have much in the way of test equipment (jumper wires, test lights, etc.) I do have a multimeter and that's about it, if that's even required for the test you describe). Before moving on though, I'd like a couple questions answered please:
1. I mentioned I did a spark test using a spark tester, and that observed spark from each plug wire. If the ECM is bad or if there is an open/short circuit in the yel/grn wire as described, could I still be getting the spark I observed?
2. Could this cracked distributor part (a sensor I understand) have anything at all to do with getting the code 15? http://s207.photobucket.com/albums/s...psacf2eab4.jpg

 

1) Something is causing code 15. It may be the fault is internal to ECM, but to find out requires some testing or replace ECM to see if that's the problem.

2) I don't see how damaged sensor has anything to do w/ Code 15.

good luck

 

Okay, I got the car to start. And I really didn't do anything that I know of to make it start. But it only started once, and now, trying to start it again, it is back to the same cranks and maybe will chug a time or two, but only cranks but will not start. And I no longer am getting any codes.
In regard to the code 16 (fuel injectors) I mentioned I was getting (in addition to the code 15), I figured the reason I was getting the code 16 was because last week when I was doing the spark test with the spark tester I decided to unplug the injector resistor connector while cranking the engine to prevent flooding during the cranking/testing, and so the code 16 was probably still stored in the ECM and hadn't cleared because I never actually started the car and got it running since the test.
Here's the sequence of events since I last posted:
I went ahead and reinstalled the ignitor after having it tested today (it tested good).
I decided to clear the codes stored in the ECM. So I disconnected the negative cable from the battery for 30 seconds or so, then reconnected. Then I checked for code(s) again, and there were none.
I decided for the h... of it, I'll try starting the car. And what do you know, it started right up, easily. I let it run a little while, then shut it off a while. Then tried starting it again after a while. But no, it was right back to the exact behavior of cranks, chugs maybe once, but then just cranks only and but will not start. I checked for any codes again, but get none.
Needless to say I'm baffled. It seems a good sign that the car did at least start (although just once), and that there is no code 15 (or any code) now.

 

Despite all your random work, you are still no closer to solution. You need to know if fuel or spark is the problem. Spark appears to be likely, but you need confirmation that spark is missing when no-start is present.

Also, you never confirmed whether the fuel pump comes on and runs for 2-3 secs and goes off. This is fundamental for fuel pressure. If fuel pump doesn't run car won't start.

Have you performed starter fluid test to see if engine will start/run briefly w/ starter fluid?

Progress requires a logical approach, not just randomly checking/chainging parts.

good luck

 

Texas, I agree that I am no closer to a solution and that I need to know if spark or fuel is missing when no-start is present. I do not agree, however, that my work has been an approach of "just randomly checking/changing parts". It won't hurt to present the actual sequence of events here, for review.
1. Several weeks back, I was informed of this no-start issue, so began attempts to troubleshoot. When I tried starting the car, I got the cranks but no-start result. Upon some initial glancing at the spark plug wires, I noticed a rather obvious cut-like tear halfway through the coil wire to the distributor. I don't know how/who tore it like that, but nonetheless it was torn through to the center right next to its boot that fits on the distributor end. It seemed logical (to me) this could be source of the issue, so I purchased a replacement wire, in fact a whole new set of spark plug wires with coil wire included, and installed them. Result: No change/improvement in no-start condition. The torn coil wire, although highly suspicious to me as the cause, was apparently not the cause.
2. Next I started researching/googling for common reasons for the crank but no-start issue. I discovered that the main relay is notorious for failing in these vehicles, and my the symptom of crank but no-start seemed to match the description, and so (to me) seemed perhaps worth considering as the next logical culprit. So I removed and at least checked the appearance of the main relay (I wouldn't say as a "random" endeavor) and did discover cracks (or "dry joints") in the soldered contacts, several of which quite obviously matched just what is shown/described in the following the guide I found while researching: When the Main Relay goes bad
It seemed logical for me to either replace the relay, or have the contacts re-soldered as described here: Relay Repair So I took the relay in to a local electronics repair person to see if he could re-solder the bad/poor joints on the board for a reasonable price. He re-soldered it quite nicely/professionally just as described in that repair article. I reinstalled the repaired main relay and the car started right up. I assumed that solved the issue, because the car started. But the next time I tried starting (the next day), I was back again to the crank but no-start condition. It crossed my mind that maybe the repair of the relay was insufficient, but further reading about it indicated that it was indeed doing its job, as I could definitely hear the fuel pump come on and run for 2-3 secs and go off when turning the key to on (and I continue to observe this, each and every time I try starting).
3. I decided next it wouldn't hurt to inspect the distributor cap; I hadn't even done that yet. I thought maybe, (so perhaps randomly now) there was something like it was cracked or bad contacts or whatever in just bad enough to cause this apparently now intermittent crank but no-start issue. The cap looked fine, the terminal contacts perhaps a little worn and used looking, but generally fine. The rotor, however, had an area on its contact that looked burnt or charred; here's a picture of it: http://i207.photobucket.com/albums/b...psc5f2a38e.jpg I live in a small town and neither of the two local parts stores happened to have new replacement rotor, so I ordered one. Meanwhile I tried filing off the charred-looking deposit on the rotor with a fine file, and managed to clean it off back to the bare metal. I reinstalled the cleaned-off rotor, and the car started right up. Again, I assumed the issue was solved. But the next time I tried starting, I got the crank but no-start issue again. As a side note here, I noticed (when I had the distributor cap off) the cracked sensor as I've mentioned; and here's the picture: http://i207.photobucket.com/albums/b...psacf2eab4.jpg
Also, I have since replaced both the rotor with the new one that arrived, and also I replaced the cap with a new one too, as just a prudent thing to do (logical? maybe not, not sure, debatable I suppose).
4. To me it seemed logical to do a spark check next. I borrowed a spark tester, this one: http://i207.photobucket.com/albums/b...psda40f17a.jpg With the tester I checked for spark output from all four spark plug wires while an assistant cranked the car. I saw spark from each, hard for me to describe the exact color or intensity but nonetheless I did see spark. Not sure if I had the tester gapped open as far as you're supposed to, but I gapped it to the specified gap of my spark plugs which is .044. While doing the spark test (cranking), I unplugged the fuel injector resistor as a method of preventing flooding the cylinders with fuel. I figure maybe that's why I encountered (later) the stored code 16 from the ECM (which has since cleared).
5. So, getting spark, its apparently logical to then check for proper fuel delivery. I know the fuel filter hadn't been changed for ages, and that the car had been driven frequently with hardly any gas in the tank and allowed to run out of gas a time or two, so I thought maybe the filter was dirty/clogged with old sediment or whatever. I thought it worth changing, not as a random measure here, but a logical move perhaps; it was high time for a fuel filter change anyway. I know it would have been more logical to try spraying starting fluid into the air intake first, as a fuel delivery problem check, but I didn't have any handy. I had a can at work and but forgot to bring it home until day or two later. That's why I ended up changing the filter before doing a starting fluid check.
6. Meanwhile, still not having done the starting fluid check, I thought about the possibility of that cracked sensor causing this apparent intermittent no-start issue. Somebody mentioned they thought if that was the case (sensor bad) that it should throw a code. So I checked for codes, as I've described, but got no code for a bad sensor, just the code 15 (ignition output signal) and the code 16 as I've also mentioned. With the information that a code 15 can mean a bad ignitor, or short/open circuit to the ignitor, or bad ECM, I thought perhaps then a logical move might be to check the ignitor first, because I know they have a tester for ignitors and do that for free at the auto parts store. What didn't seem logical (to me) though, was that I was testing for a bad ignitor even though my spark test revealed I was getting spark. But I had the ignitor checked anyway, and it checked out fine.
7. Before reinstalling the ignitor, I decided to clear the OBD codes, just to make sure I'd be starting fresh again with no stored codes. Then I installed the ignitor and checked for any code again. There was none. I tried starting the car, and it started right up, easily. Next time I tried starting the car, I was back to the same cranks but no-start issue. I checked for any codes again, and there are none. I tried starting the car again after sitting overnight, but same thing, cranks but no-start. That's where I'm at now, and seem to be remaining. New paragraph below.

I've still yet to perform the starting fluid into the air intake test. I have a can of it but not a helper to crank after I spray. I can/will do it soon. Although the car did start already, as per my last post here, so I assume it's getting fuel okay (rightly or wrongly). Unless something is causing an intermittent improper fuel delivery to cause my issue. New paragraph below.

Probably no sense now in speculating until after the starting fluid test, but what might be the next logical step if I get no change in start-up behavior with that test? I'm thinking do yet another spark test?
Any further advice/comments certainly welcome! Thanks!

 

Clearly something is intermittent; either fuel or spark. That's why it's essential to perform the main fuel relay check (listen for fuel pump) and check for start w/ starter fluid when no-start condition is presented.

We have seen instances of spark that could be seen, but would not start the car. Weak coil (internal short) is usual culprit.

It could also be an intermittent ignition switch assy.

Isolation of fuel or spark reduces the number of possibile faults.

good luck

 

To update, I just had the opportunity to try to start w/ starter fluid as suggested. While spraying generously into the air intake, I had an assistant crank the engine, with no effect/change of my crank but no-start symptoms.
In regard to the main fuel relay check, as I previously mentioned, I definitely hear the fuel pump come on and run for 2-3 secs and go off when turning the key to on (and I continue to observe this, each and every time I try starting).
After this last attempt at starting, I again checked for any codes, and there are none.
If a weak spark is happening, obviously it must have been strong enough to start the car last night, so it seems if spark is weak enough to prevent starting, it must be happening most of the time but not all of the time.
I can try spark testing with my spark tester again, maybe this time widening the gap (maybe up to an inch or so?) so as to see a possible stronger-looking spark. I can try to check coil output as well. And I can consider intermittent ignition switch assy as suggested, also. I'm somewhat relieved that I'm not getting code 15, but am rather mystified why it was there in the first place. Regardless, this feeling I am no closer to a solution is very discouraging. But thank you and I do appreciate your patient replies and helpful suggestions so far.

 

This thread is getting long, so I skimmed through it.

There is a ground on the thermostat housing under the distributor. Disconnect that ground, clean the eyelet and bolt with a wire brush or some sand paper, then reattach.