walkngdude
NAXJA Forum User
- Location
- Santa Cruz California
Hi,
I have a 1992 Cherokee with a manual transmission. The other day it was running great and had been for a while. I recently replaced the water pump and shortly before that I had a shop do U-Joints, thermostat and power steering pump.
Like I said it was running great and I turned it off and parked it and came back a few moments later and it cranks strong but wont start at all. I get it home and try again and the starter cranks fine but no start and I can smell gas.
So I check for spark at the plugs and nothing. I put a multi-meter on the coil primary with the ignition on and I have 12 volts between positive and negative terminals on the snap-in connector. I pull the coil secondary wire off of the distributor and turn the motor over and no spark there.
I also replaced the spark plugs, wires, cap and rotor maybe a year ago.
I removed the ignition coil from the Jeep and test it with my meter. I get primary to metal body = 0 ohms, primary positive to negative = 1 ohm and primary to secondary was (I forget) but it was a lot of ohms, like 6k or 6 megs or something.
I checked the fuses in the engine compartment they all look good. And quickly looked over the fuses in the cab but didn't see anything that looked ignition so didn't get into it.
I have replaced the crankshaft position sensor and the sync signal generator module (inside the distributor).
I have a Haynes and the factory manuals and reading through the factory manual on the ignition system the only device that it specifically says the engine will not run without is the crankshaft position sensor. So I haven't gone through and tested the other sensors: Coolant Temp Sensor, Manifold Air Temp Sensor and Manifold Absolute Pressure Sensor.
I might have access to borrow an ignition coil tomorrow to test it or I can buy one for $70 but I think that it looks good. But if it's not bad and I have power to the coil primary would the lack of the Engine Controller interrupting the the primary negative on the coil make it so that I don't see a spark? (I say this because the manual says that the Engine Controller controls the timing through the negative of the coil's primary.) So maybe the Engine Controller isn't pulsing the ignition coil's primary and a steady coil output would do what to ground? IDK.
So what could I be missing here? Where to look next? Replace the coil or Engine Controller?
Any help would be highly appreciated.
Thanks
Marc
I have a 1992 Cherokee with a manual transmission. The other day it was running great and had been for a while. I recently replaced the water pump and shortly before that I had a shop do U-Joints, thermostat and power steering pump.
Like I said it was running great and I turned it off and parked it and came back a few moments later and it cranks strong but wont start at all. I get it home and try again and the starter cranks fine but no start and I can smell gas.
So I check for spark at the plugs and nothing. I put a multi-meter on the coil primary with the ignition on and I have 12 volts between positive and negative terminals on the snap-in connector. I pull the coil secondary wire off of the distributor and turn the motor over and no spark there.
I also replaced the spark plugs, wires, cap and rotor maybe a year ago.
I removed the ignition coil from the Jeep and test it with my meter. I get primary to metal body = 0 ohms, primary positive to negative = 1 ohm and primary to secondary was (I forget) but it was a lot of ohms, like 6k or 6 megs or something.
I checked the fuses in the engine compartment they all look good. And quickly looked over the fuses in the cab but didn't see anything that looked ignition so didn't get into it.
I have replaced the crankshaft position sensor and the sync signal generator module (inside the distributor).
I have a Haynes and the factory manuals and reading through the factory manual on the ignition system the only device that it specifically says the engine will not run without is the crankshaft position sensor. So I haven't gone through and tested the other sensors: Coolant Temp Sensor, Manifold Air Temp Sensor and Manifold Absolute Pressure Sensor.
I might have access to borrow an ignition coil tomorrow to test it or I can buy one for $70 but I think that it looks good. But if it's not bad and I have power to the coil primary would the lack of the Engine Controller interrupting the the primary negative on the coil make it so that I don't see a spark? (I say this because the manual says that the Engine Controller controls the timing through the negative of the coil's primary.) So maybe the Engine Controller isn't pulsing the ignition coil's primary and a steady coil output would do what to ground? IDK.
So what could I be missing here? Where to look next? Replace the coil or Engine Controller?
Any help would be highly appreciated.
Thanks
Marc
