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I replaced the 4.0 motor in my 93 jeep grand cherokee with a 95 cherokee 4.0 it will turn over but is not getting spark did jeep change something between those years that would cause this? I've put all the parts (distributer,coil,etc) off the 93 motor that was running. I'm at a loss any help would be appriciated  

both years are crank trigger ignition...   the crank sensor is near the flywheel on the side of the transmission bell housing.....


the distributer housing is not adjustable....    the distributer has to be inserted so the rotor ends up pointing at the #1 wire in the cap...   standing beside the car... looking in at the rotor... 5  oclock position...   this is with the number one cylinder at top dead center on the compression stroke... and the timing marks lined up on the balancer...

if this is off.. the crank sensors signals to the ecm will be confused by the cam sensors out of sync signal... so nothing will happen...

are you getting spark from the coil??????   if so..    will the coil wire throw a 3/4" spark...  position the coil wire... don't hold it with your hand...    i have had coils go bad ... still spark ...  but not enough  to start the motor...

so many things it could be...

spark...   from the coil...   to the spark plug ends of the wires....

fuel pressure...

air...

GROUND WIRES>>>>>>>     NO grounds   no start... i am not talking about the ground from the battery.. i am talking about the ground wires that connect to the computer...   the computer is only grounded to the engine block.. NOT TO the body or the battery... only to the engine block..   the body is grounded to the engine block...   the battery is grounded to the engine block...   so all the wires have to work...


why not see if you get some trouble codes out of the computer...

Entering the self-diagnostic system on models prior to 1991 requires the use of a special adapter that connects with the Diagnostic Readout Box II (DRB-II). These systems require the adapter because all of the system diagnosis is done Off-Board instead of On-Board like most vehicles. The adapter, which is a computer module itself, measures signals at the diagnostic connector and converts the signals into a form which the DRB-II can use to perform tests. The MIL or a scan tool can be used to read codes.

Remember that the fault message identifies a circuit problem, not a component.

MIL Method
This procedure may be used on 1991-96 models.

Start the engine, if possible, cycle the transmission selector and the A/C switch if applicable. Shut off the engine.

Turn the ignition switch ON-OFF, ON-OFF, ON-OFF, ON within 5 seconds.

Observe the MIL on the instrument panel.

Just after the last ON cycle, MIL will begin flashing the stored codes.

The codes are transmitted as two digit flashes. For example Code 21 will be displayed as a FLASH FLASH pause FLASH.

Be ready to write down the codes as they appear; the only way to repeat the codes is to start over at the beginning.

autozone.com does have online repair info for free on this jeep model...

here is a component locator... i take it that you do have port fuel injection.. not throttle body fuel injection,,

http://repairguide.autozone.com/znetrgs/repair_guide_content/en_us/images/0900c152/80/0a/9b/5e/large/0900c152800a9b5e.gif

post what you find...  post what you did...   which parts went on which motor...