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Okay guys,
I haven't posted here in forever, but I need some help from the bright minds of the Mx-3 community. I am not an idot and have checked all the simple things and KNOW that I have Spark and Fuel and I have pulled the timing cover off and verified that the timing is correct. With that said:

I have a 93 GS with a Straight Neck ZE with HEI mod. The car turns over strong, but doesn't even act like it wants to fire. There is one very strange symptom that I haven't been able to explain yet. When cranking I have heard and seen a puff of air shoot out of the o-ring that surrounds the fuel injector at least on the number 1 cylinder. I took the fuel rail off and checked the o-rings and they look fine, I tightened everything back up and it still does it. Lastly, the week before the car finally died for good, it totaly shut off on me while driving down the road in gear with throttle applied (not a stall). There were no strange noises just a clean shut off as though I cut the ignition off. I noticed the Tach signal bouncing around just before that happend. Now for the ever growing list of thing I have tried:

Tested Spark...Good
Getting Fuel in all cylinders (Correct Quantity???)
Pulled fuel rails and watched spray patern while cranking...Good
Timing verified by timing marks on cam gears and crank pully (Double checked rotor button position on distributor)
Bought and installed new spark plugs
Verified spark on all plugs by grounding them and cranking...Good
Installed known good plug wires
Checked all my grounds and cleaned up one that was iffy.
Checked all my fuses
Installed a known good MAF
OHM tested the resistor for the HEI...Good
Checked all wiring going to the HEI and ensured it was well grounded
Installed known good Distributor and wired it back to stock plug. (HEI problem ruled out)
Installed K8 ECU (grasping at straws) Still wouldn't start.
A buddy brought an expensive diagnostic computer from his shop and we back probed the crank and cam sensor plugs and both seemed to be giving proper signals.

Summary:
I have tried everything that I can think of and probably some things I have forgot to list. The symptoms the car was having before with what appeared to be the loss of the Tach signal make me think that this is still where my problem lies. But I don't know what to test. I have tried two different distys so the cam position sensor shouldnt be the issue. Can you put a multimeter on the line running out of the disty, or into the ECU and read a change in current while cranking... is that a possibility? I am just all out of ideas and really want to get my car running. It is frustrating to not know what to try next. Please thow out any suggestions no matter how off the wall. I am desperate.

For what you say, it looks to me like your timing is 360* off.

I know you said you checked the timing, but that's only half the equation. The camshafts make 1 turn, for every 2 turns of the crankshaft. If your crankshaft is in the right position, but "in the wrong turn", the spark from the distributor will be going to the wrong cylinder, and the engine won't start.

Make sure that, when all the timing marks on the cam sprockets are aligned properly, the distributor rotor is on cylinder 1.

I know that that is a common mistake when people are changing a timing belt, but its very unlikely that you could jump proper timing exactly 360* but that said I did check for that when I did it. I will update my post.

Thanks for your reply.

I'd double check it if I were you.
Nothing else makes sense. If you have spark and fuel (and you obviously have air), the engine should at least try to work. If you're getting nothing, the only possible reason is that one.

Try holding down the throttle for 2 seconds before you start the car, and holding it while you crank it... It may sound stupid, but I've had to do this on 3 occasions where no amount of patience or waiting allowed my car to start. N

I will check it agian and I agree with you...To me there is no logical reason why it shouldn't try to fire. That is why I am reaching out to you guys. The thing I keep comoing back to is why is there a puff of basically exhaust out of the fuel injector o-ring. The only things that makes sense is that the exhaust is plugged up somewhere or the exhaust valve is stuck shut. That said, I am going to pull the intake and rear valve cover and see what I see. I already pulled the front and everything looks in order.

Also, I pulled both O2 sensors off the headers and had my wife crank while I felt the exhaust exiting the O2 bung so its not that clogged up. Couldn't swear that they were all exhausting though.

Upon installing a klze in mooneggs car we had spark and fuel but it would not start. The only thing we changed was install of a probinator ecu and the motor car ran fine with the k8. So after much diagnosis I deemed it was the ecu even though he was insistant that it was good we exchanged it and fired right up. I would check your ecu for codes or replace with a known good one, odd that a car can have fuel and spark and not start but if the ecu thinks that it is supposed to fire at a different time then it wont start no matter what.

With the tach part bouncing around on mine that happened because the 1k resistor to the 4 pin module broke off to the hei mod. worth a look.

If you have an external coil have you tested that?

ccreech wrote:Installed K8 ECU (grasping at straws) Still wouldn't start.

ccreech wrote:OHM tested the resistor for the HEI...Good

ccreech wrote:Installed known good Distributor and wired it back to stock plug. (HEI problem ruled out)

Have you tried my suggestion yet? Picture yourself testing a fuel pump in a carburated car the lazy way. Pour some gas in the carb and crank it... if it starts then dies it's the sending unit, or fuel system rather... could be anything in there.

The application here would be to try and flood the engine slightly, so pump the throttle a few times before you try to start her up. Sounds stupid? maybe... couldn't hurt to try it though, eh?

Unless the MAF is sensing more airflow, pumping the throttle is not going to add anymore gas than the computer tells it to add for cranking. The only thing pumping the throttle on an EFI car might help with is letting a little fresh air in through the TB. I have pulled the plugs after a round of heavy cranking and the plugs were actually wet, so if anything I am getting too much gas, but I don't think that i am. I think it was just a lot of cranking with no combustion.

Oh and I have done a compression check on all cylinders.

Then you just answered your own question. You have spark, fuel and compression. It HAS to be the timing.
Having spark means your whole electrical system is in good shape (or, at least, good enough to have spark ), having fuel means your fuel system is also good, and compression is the 3rd part of the equation. You can assume you have air (you sure you didn't forget a shop towel inside the TB, aren't you? ), so timing is the only possible culprit.
Check it out. I'm sure you'll find your timing all screwed up.

my klze had the EXACT same problem when i first went to turn it over.. the timing was out pretty much a full 360 degree's. re-timed and it fired up no problem...

ccreech wrote: Also, I pulled both O2 sensors off the headers and had my wife crank while I felt the exhaust exiting the O2 bung so its not that clogged up. Couldn't swear that they were all exhausting though.

I agree
Double check your exhaust isn't plugged (have you pissed anyone off lately lol ), after that ignition timing so check that with a light to see if it's even close to 10 deg TDC and finally ECU. Our ECU's are pretty dependable though.

If the car was running but now isnt running how can it really be timing because there is only 1 way to put in a distributor and it more or less self times itself. unless the belt jumped timing i'm not entirely sure it would/could still be timing.

Also, how does the area around your crank pulley look? i would look at your crank position sensor to make sure the wire hasnt slid down and been rubbed through that would also be another big issue to cause it to not start. Is all the wiring for the hei mod in good shape?

there is only 1 way to put in a distributor and it more or less self times itself.

wrong? lol... the way u time these motor's is to turn the distributor to a certain point.. so no its not self timing, and no there isnt only 1 way to put it in.. lol. love to see how your cars running.