1991 Jeep Cherokee ignition coil

1991 JEEP CHEROKEE
184,000 MILES • 6 CYL • 4WD • AUTOMATIC
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CANTU123456
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i have a 91 jeep cherokee. its been running fine but one mourning i went to start it but nothing. it cranked and sounded like it was trying to fire. its getting plenty of fuel, I pulled a plug to check for spark and at first when i cranked it there was no spark then a few seconds later it sparked but not like it should have. its spark doesnt fire as quick as it should its like every couple of seconds or so it sparks./
Is it the ignition coil? and if so what should the voltage outuput be for the ignition coil when cranked?
Feb 25, 2010 at 1:15 PM
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JDL
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Hi, thanks for the donation. I'd check for trouble codes, first. You may be able to get mil codes by cycling the ignition switch. You turn key just till dash lites come on, no further. Cycle the key, on--off, on--off, on--off, on, then the mil starts flashing, you count the flashes to get the codes. Your looking for two digit codes.
Feb 25, 2010 at 2:15 PM
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CANTU123456
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[quote:941ec0386b="jdl123"]Hi, thanks for the donation. I'd check for trouble codes, first. You may be able to get mil codes by cycling the ignition switch. You turn key just till dash lites come on, no further. Cycle the key, on--off, on--off, on--off, on, then the mil starts flashing, you count the flashes to get the codes. Your looking for two digit codes.[/quote:941ec0386b] I pulled off the codes and got 12 and 21. my battery cable going to the positive, the wires are farely burnt goin up to the post could that cause the delay in spark?????
Feb 26, 2010 at 9:18 AM
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JDL
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I'd probably replace all battery connections. The code 21 is o2 sensor. Where applicable, if voltage to 02 heater circuit, has a problem, it can cause voltage problems on other systems.
Feb 26, 2010 at 12:23 PM