1990 Jeep Cherokee

Electrical problem
1990 Jeep Cherokee 6 cyl Four Wheel Drive Automatic 210000 miles

1990 4.0 cherokee with 1994 4.0 grand cherokee engine. Never has ran since the swap. Wasn't getting spark til I ran jumper wire from coil. Still turns over but no crank.
April 14, 2009.

Disconnect a sparkplug wire or 2 and ground it to the engine -have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs, distributor pick-up coil, ignition control module, ECM, Ignitor cam and crank sensors- Note: If it doesn't apply disregard it

Apr 14, 2009.
It sounds to me like a bad pick-up coil but you do need to check fuel pressure should be 40-45 psi when you turn the key on

Apr 15, 2009.