Topic: its dead

[bumati]

Went out and started Jeep. Let it idle a few. Died. Ok checked fuel line that's good.  Next was
the ignition system.  Replaced coil cap rotor and plugs (yes I have spares).  Nothing. 
Not a damn thing.  No spark.  Rotor is spinning.  What next?  I am stumped.

[FourbangerYJ]

coil wire? Crank position censor?

[bumati]

Replaced coil wire.  Cps?   Not yet

[sharpxmen]

when you crank it do you hear the fuel pump? do you get 12v at the coil (when you crank it)?

[bumati]

Eliminated fuel with starter fluid test.  Got a new cps. Putting it on now.

[bumati]

What am I missing?   Ecu?

[aka-justin]

What's the year and model?


My friend's Cherokee did a similar thing, ended up being a ground problem to the PCM.

[bumati]

95 yj with 2.5

[sharpxmen]

Eliminated fuel with starter fluid test.  Got a new cps. Putting it on now.

that doesn't mean anything, you might not have spark nor fuel. Without any tests is hard to tell unless you want to troubleshoot by replacing items.

[bumati]

Poured fuel down intake.  Not so much as a pop or crackled.   Spark?   Tough
to check by yourself.  But. From what I see no spark. 

[bumati]

With the help of neighbor he cranks I checked for spark. Nothing.  I checked power to the coil. Nothing.  Still stumped.  What's left?

[Jeffy]

Time to get out the VOM or test light.  You didn't saw how long it idled for before dying either.  It sounds like it's going to be either two independent issues or a bad ground or PCM.  You're going to have to test for each.

• Check for stored codes in the PCM?
• When you turn on the ignition does the seat-belt and CEL turn on and then turn off?
• Instead of just bypassing the fuel pump, listen for it.
• Check the Camshaft Position Sensor in the distributor?
• Check all of the fuses in the PDC?
• Check all of the relays in the PDC?
• Check the ground on the PDC (6BK)
• Check both grounds on the PCM. (#11 & #12 16BK)
• Check the signal ground on the PCM. (#5 16BK)
• Check the coil driver on the PCM. (#19 18GY)
• Check the Relay Coil signal on PCM. (#15 18DB/YL)
  

[bumati]

Let it idle for a minute.  It died sharply no stuttering.  No codes. The seat belt light comes on and goes out. Check engine light no not at all.  Cannot hear pump but never could.  Will listen tomorrow.  Fuses in pdc are all good.   Have a different pcm/camshaft position sensor  arriving tomorrow.  Will run test then.   Thanks

[sharpxmen]

Let it idle for a minute.  It died sharply no stuttering.  No codes. The seat belt light comes on and goes out. Check engine light no not at all.  Cannot hear pump but never could.  Will listen tomorrow.  Fuses in pdc are all good.   Have a different pcm/camshaft position sensor  arriving tomorrow.  Will run test then.   Thanks

check power to the ASD and fuel pump relay. If you don't have power to them then replacing sensors won't help, that's my guess - with the contact off you should have 1 prong with +12v, with the contact on you should have 2 of the relay prongs with +12v, if you don't check fuse 5 in the fuse block under the dash (left side of steering wheel). the Cam sensor will not give you spark or power to the coil, that's the crank sensor, the cam sensor only gives signal to synchronize the injector opening.

[Jeffy]

Hmm no CEL and Brake light when starting up?  I believe that's when the PCM goes though it's diagnostic.