yep, sure do. Wonder if ICM could be causing ineffective firing.

 

""""""""However if i pull the coil wire and crank it for a bit...then plug it back it and start it...it will run for 5-7 seconds..."""""""

Couldn't happen 180 out.

If the spark looks good while doing it, it's NOT ignition or PCM.

cranking most sensors are not in play.

pull the plugs, blow lots of compressed air in each cylinder to dry them out. Install another set of NEW plugs, start it up and enjoy.
OR do the trick.

No matter how many sensors or computers you put in, IT WILL NOT START WITH WET PLUGS.

 

check compression. i had the same thing happen to me, dont freak out by the vehicle, in my honda and come to find out i was losing compression in a couple cylinders.

 

Its worth a shot I guess. Never had the dist out and I also checked #1 cyn at TDC and it looked right on....was thinking jumped timing. The weird thing is that when I pull the coil wire and let it crank (allowing injectors to pump fuel with no spark) then reattach coil and then turn it over...fires right up and for the brief time it runs (burning up fuel I cranked in) runs and sounds beautiful! Smooth,,,no sputtering or knocking or tapping....sounds awesome. So I can't figure out if its not getting enough fuel through injectors or not....carboned up plugs mean too rich or not sufficient spark right? I'm not new to mechanics so I do make sure basic stuff like proper gap and grounding are true....just new to RENIX...lol. WHOEVER FIGURES THIS OUT FOR ME IM GUNNA SEND A HUNDRED BUCKS!!!! I aint kidding....im frustrated.

 

I appreciate the reply and help rrich...but if the jeep has been sitting for days or even hours, the plugs and cylinders should be bone dry....right? When I turn it over it fires but wont stay running....as if it's starving for fuel. So I pull coil wire and crank it , allowing injectors to pump fuel in....then try again right away and it fires right up and runs,,,,if it needed dried out, it wouldnt start up that way. I have good fuel pressure,so my thought was injectors arnt delivering enough fuel to keep it running....because as I open throttle....introducing more air...it shuts right down...too much air not enough fuel??? But looking at my plugs suggest the are not firing sufficiently....so IDK. I think I'll get a new pick up coil and pull the dist and replace it...maybe the injectors arnt getting proper signals to fire. Anyone know how to test the pick up coil with voltmeter???

 

"""""""""but if the jeep has been sitting for days or even hours, the plugs and cylinders should be bone dry....right?""""""

Only if the plugs are out and air can get in. Else it can stay wet near forever. You';e said you've been playing with it for a long time, plenty of time to wet the cylinders.

The black soot is carbon - from only partially burning. Carbon is conductive - when the plugs have carbon on them it shorts the spark to ground, no spark=no fire.
Brand shiney new plugs installed immediatly foul when the piston circulates the carbon onto the plug - shorting out the new plugs.

Try the towtruck driver's trick - see if it helps. It usually can fire fouled plugs that aren't too fouled.

IF not, pour about 2 teaspoons of fuel down the TB as "prime" - if it tries to start then, it proves it is too lean/starving for fuel.

Then check intake vacuum at cranking speed. Or at least hold your hand over the TB to see if it's got good suction while cranking. You can even try starting it with your hand choking off the TB - If it starts, proves it's too lean - air is getting in somewhere else.

Then a smoke test would be appropriate if it tried to start with the prime or choked.

Most sensors are not used when starting - back to basics - air, fuel, good spark at the riight time, and compression.
Color of the spark is important- shows voltage and ability to start a fire.

If you have a good spark that shows the pick-up coil is working.
Low compression in even several cylinders won't keep it from starting - just runs bad when it does.

Near 0 compresion in ALL cylinders can keep it from starting - checked it?

Next step - need to make sure the spark is just before TDC - a timing light will show that when cranking.

 

Ok...I'm gunna try the tow truck driver trick....and also pour a little gas in TB. Now I noticed when I access the throttle body, I see the butterfly is completely closed...normal right? I have to manually open it to spray starting fluid in it. Does run briefly with starting fluid....backfired through carb too. Whats up with that?

It's pouring out right now...have to try later.

 

Be sure to note the COLOR of the spark.

The plates are normally closed all the way, the IAC provides the little bit of air needed to idle.

running with starting fluid - or gas says lean - backfiring when lean can be expected.

when lean, it needs a good spark and plugs that are not fouled.

lets say a big vacuum leak makes it lean, has trouble starting. cranking and cranking puts fuel in - but as it accumulates fuel - squirting each time it fouls the plugs. Then it has a double problem - lean and fouled - or carboned up from trying.
signs are pointing that way.

 

Hmmmm...makes sense. Off to work for the night, but def gunna look for major vac leak tomorrow. Thanks rrich

 

I know one time i was workn on a no start on a subaru that had twin timing belts and wouldnt start . I cked and cked those belts and timing would almost fire up tryed putn drops gas in intake would pop back come to find out be fore it got to me some one replaced the starter and the starter windings was wound backwards lmao so i put new starter on after countless hrs of diagnostix and it started up. Hope u get urs goen