89' Jeep Cherokee Pioneer intermittent spark/no spark.HELP!


#1

will turn but not start and it sparks rarely but not enough to fire daughter(me) just rebuilt head gasket in engine please need help asap only vehicle!!! and could the white ceramic square (maybe resister) that has two wires in it that attached to the left side of the engine like a ground have anything to do with it? its broken but the engine still turns help me


#2

Do you have a repair manual to be sure of the spark plug wires routing? Start with new spark plugs and wire, distributor cap and rotor, air filter, and pcv valve. Maybe, it’s a fuel problem (delivery to the engine and injection)? Check for steady electrical power (12 volts). Look at this web page http://www.autozone.com/az/cds/en_us/0900823d/80/15/3e/8f/0900823d80153e8f/repairInfoPages.htm Click on Fig.26. With the ignition in RUN, power goes out to the alternator, ignition control module, fuel pump relay pull-in coil, O2 heater relay, and the PCM (engine computer) over a yellow wire. Use a voltmeter to check for 12 volts on the yellow wire on the distributor. As you are reading the voltage, shake the wiring around. If the voltage meter indication jumps, there could be a poor connection, a short, or a partially broken wire.


#3

The resistor is designed to cut the voltage to the coil when the key is in the RUN position.

You should have 12 volts at the coil when cranking the engine and approx. 6 volts when the key is in the RUN position. A failed resistor usually means the engine may cough when cranking it over, but will die the minute the key is released from the START position.

If the resistor is burnt into (a common problem with Chryslers) then it will never run. Replace it; they’re cheap.

If you want a test, simply run a jumper wire from the battery positive post to the ignition coil positive terminal. If it starts and runs you know the resistor is the problem.
(And of course, do not leave it like this.)


#4

The crank angle sensors are a common failure with these vehicles. Yours may be flakey.