Good Crank, No Start

I have a problem that I hope someone can help me with. 1999 jeep Cherokee 4.0 Started up and drove around town normally ,no hesitation, misses or backfires. Cut jeep off ,sat in driveway a few hours listening to tunes. Next morning car would crank strong but would not start. Checked battery, It was normal for prolonged starting attempt. hooked charger up for a couple of hours. Tried again, good crank, no start.

Checked coil with spark plug to ground, good sequenced spark. Checked individual plugs, good spark. Placed screwdriver in choke and sprayed starter fluid. No signs of start. I have noid lights but I figured if starting fluid down the throat wouldn’t do it. Its not a fuel problem, Engine wasn’t missing a beat before This it’s a daily driver for a retiree. Head replaced January ’16 . Fuel injector changed in summer of “16 for upgrade.
There is no check engine light. Oil changed on time , No overheating last summer.. Only (smal problem l) fuel rail wouldn’t hold fuel. Had to use double key trick to start. Strange, remote start started right away. (Curious) not a problem though. Fuel pump change a year ago..
Permanent fuel pressure mod on fuel rail..

Do you have an alarm or anti theft system?

Thanks for your prompt response ,Yes I've had a Viper 5901 since 2000. Alarm, Doorlock,unlock and remote start. Other than changing remotes due to dropping and drowning. Haven't had any trouble. Spoke to Alarm installer,and was told that if alarm was defective, starter would not work??? Does this sound correct.

It might be, but with the symptoms you describe, it is not uncommon for anti theft devices to permanently cut off the fuel, since that is what they do anyway. I have heard of several on this forum that did what you describe.

I will check further,Shouldn't starting fluid have any effect, along with spark?What does the roll over relay cut off?

if you mean ASD relay, it cuts off the fuel and part of the ECM. You cannot flood it with ether and get it to fire. Just some vapor does the trick

IIRC Viper cuts out power to the lead to the starter relay (solenoid), not fuel. When Viper is in alarm mode you won't be able to crank. Fuel cut off sounds like the factory anti theft system using a 'chipped' key. If you have had to use the two key trick in the past, that points to the factory anti theft system as the source of your issue.

Yes thank you,Charlie Foxtrot,that verifies that. I can crank strong so may not be alarm, car never had factory alarm to my knowledge. I was doing the two key thing because fuel pressure went from holding 40 + psi's for hours and gradually dropping to dropping immediately after shutdown. (I have gauge permanently attached to fuel rail bleed valve.) I have a set of noid testers that I can test the injectors with but i felt that spraying starter fluid in the throttle body (held open with screwdriver) would tell me if fuel was getting to the cylinders. Maybe the valves are not opening? Nah. Clogged catalytic converter? Really? Be Real. Really. Anyway Friday,is Check Compression,fuel injectors and anything else I can find day. ( I really didn't pour it in,Just a little mist ,then a little more,and a little more. (4.0s are known for being thirsty) Thanks All.

I kept cranking and finally got jeep to start. It caught and blew out black soot smelling like starting fluid (ether) I did have to play with gas pedal a little bit. Once it caught, it idled without touching pedal,like normal ran without a hitch. I let it warm up,then goosed the motor, highly responsive as usual, No backfires ,no hesitation, Let jeep run for couple of hours (trying to burn through 1/2 tank of gas.) turned motor off. Put two bottles of STP gas treatment in tank. started Jeep again same difficulty. Had to horse motor to start once started ran like top. jerked jeep back an forth to mixed gas and gas treatment. Jeep responded fine. Let run for another hour. Noid light test worked fine. I will Seafoam soon. I'm sure I could leave ten feet of rubber if necessary. Its pulling strong. Just very hard starting. But good cranking and may have slow short circuit. Was down to 10.8 after week of inactivity. During charge alarm went off twice. I was able to cancel with remote normally.Not sure if this is part of the problem. Any other ideas will be welcome. Thanks.

Did you check for spark before or after the distributor?

Sent via messenger pigeon. I talk, he types.

Good spark before and at each individual plug. After extra ling crank it finally caught,I ran a few cans of gas treatment through and now it runs. Have no real idea what is diferent,maybe it was bad gas.

Must be gremlins :D