My brother has a 1991 Jaguar XJS that won’t spark on either bank. I checked/tightened all grounds, charged the battery, and it fired- ran for 5 minutes. Now, it’s back to not starting; no pulse from the brain to the coils. Suggestions?
Since you say it won’t spark on either bank I’ll assume you’re dealing with a 12 cylinder engine. Since it’s a 12 cylinder it has 2 coils running on essentially completely diffrent circuits. If neither of them is producing a spark this would indicate a problem with the ignition switch, or the crankshaft or flywheel sensor, something like that.
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