I just replaced my head gasket today do to the fact that my freeze plug had a rust hole in it. That all went well. But before i started on it i tried to start it up and it would crank but wouldnt fire. I put that issue aside and went ahead and did the head. I got it all put back together and it still wont fire. Its getting fuel, i replaced the coil, and the distributor is doing what it should. But im not getting spark out of the coil. Im not sure on whats going on? Is there a relay or anything that wouldnt allow it to get spark? Im stumped! That i know of all of my grounds are connected. Like i said it did this before i did my head gasket. And the only place its been since january is backed out of my garage for a bath and thats it. And before last week it ran fine besides the hole in the freeze plug. Any suggestions will help out i really want to get it back on the road.

 

How about power to the coil, anything there? Try swapping the ASD relay with another?
Anything happen to the CPS or wiring? Has it ever been changed?

 

X2 on the cps. If you don't have power to the coil id be about 78.54% sure its the cps

 

I agree with the others that the crankshaft position sensor is a primary suspect. First though, try swapping the ASD relay in the power distribution center with a non-critical relay like the e-fan. The relays are all the same part number, so swapping is not a problem. And verify all fuses!
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Spark: 12 volts from ignition switch to the ASD relay; when the key is first turned on the PCM provides a ground to the ASD relay to energize it, then the ASD relay passes 12 volts to the coil primary side. If no crank sensor signal is generated after a couple of seconds the PCM cuts the ground to the ASD relay (and fuel pump relay too) and that cuts power to the coil (and fuel pump). Key to START and once again the PCM energizes the ASD relay. Now, a critical element is the crank sensor--no signal from the crank sensor and the PCM won't trigger the coil to provide spark.

 

where is the crank position sensor located?

 

It's in a booger of a spot. About 10, 11:00, on the bell-housing, facing forward. Changing it the first time can really suck. I can give some helpful info if you go there. Do listen to those guys, you have some of the best there. See what they say, but I'm thinking not just any CPS. MOPAR, or in my older thing Napa, Idk about yours though.

 

Only read title and I'm willing to bet a dollar its CPS. Now I will read and laugh.

 

Now I will give you a real answer. Still say CPS. You could just have yours unplugged still. Since you pulled your manifolds off you had to unhook the connector. If you did plug it back up you proly bumped or pulled on the CPS. The factory location for the plug is the back stud of the fuel rail bolt. The wire runs down to the back bell housing. Check to see if it is unplugged first. Second order you a new one and replace. You will have to do some searching for best way to swap. If you can do a head gasket, then you are capable to replace CPS. I can do it in about 20 mins.
There are many ways to replace the CPS Search and you will find.

 

Change a CPS. A jack-stand under the left frame might be in your way. Have it under the axle. You lay on your back with your feet out under the passenger side. With your LEFT hand you can reach up past the front drive-line to hold the CPS. (if your forearm is smaller than a quart mason jar)(if not maybe pull the drive-line). It's 7/16-or 11mm bolts on the older Jeeps. You want, socket,> 3 inch extension,> swivel,> then 18 to 24 inches of extension to your RIGHT hand , down on the ratchet by the tranny cross member. If there is a plastic deal there, can it. DON'T drop a bolt in there! (just don't!!!). When you are starting out, if you tie a long string, 5ive feet, to the old plug, you can then use that to haul the new one back up.
If your wires go through a metal band secured by an engine to bell housing bolt, cut them. To finish, zip tie, or make darn sure the wires won't rub/chafe or burn on anything. The second one is a relative piece if cake! (½ hr job!)

I'd still listen to Radi and TJ though, (and yes, see it is actually plugged in).

 

How I do mine. I am Left handed and that makes a big difference to the way I tackle things like this.

Tools I used
3/8 Ratchet
7/16 swivel socket
1 short extension
Cant remember the size of the gear select linkage (I think it was 13mm)

I got under jeep head facing passenger side front tire. vvFeet toward drivers back door.

I removed the 2 bolts holding the gear linkage for a little more space. (13 mm gear wrench I believe, Could have been socket and ratchet)

I then stuck my right hand up in front of the bell-housing (engine side).

Took left hand with ratchet short extension and 7/16 swivel socket between the body and tranny.

I used my right hand to guide the socket onto the CPS bolts and broke them loose.

Then I removed the ratchet and stuck both hands up to the extension. Left hand holding the extension and right turning the bolt loose.

When they were finger loose I used my right hand from front of bell housing and pretty much reached over the bell-housing and took them out.

Putting it back on in reverse order.

There are a ton of different ways. I found that way to work for me and took very little time.

As other might say. Be careful not to drop the bolts into the slot. could be a pain taking off the dust cover to get them out.

 

Ok thanks for all the helpful info. Im going to try to tackle it here shortly. I will let you guys know if that is the problem. I remember plugging it back in but i never checked to see if it had a loose connection. But it wouldnt start before i did the head gasket. So im thinking that it is prolly gone bad.

 

In the god awful case you drop it in the hole, not saying I've done it before :P , take out the bottom most flex plat to tranny bolt, and just pull it out. A magnet on a wire works well, so does a rubber mallet to the tranny. It will come out, just be patient while taking out the cps and you can avoid it altogether lol

 

Just a update on it.....I got to change out the cps today and it fired right up. Ran just as good as it did before. I found it easier to lay with my feet at the front of my jeep and take it out that way. I couldnt get my hands up there and see the bolts any other way. But thanks everyone for all the helpful info.