'97 Wrangler has no Spark


Thanks for your post and welcome to the forum. Hang on to the crank sensor if it's original . On auto trans I can't say the go frequently but on manual they get debris from the clutch facing . This is a factor in some no starts. Want to say as well that parts store replacement crank sensors have wreaked more havoc in certain brands and had more members chasing their tail than success. Lots of questions to ask like are the any trouble codes . Have the O2 sensors been changed . Rightfully , before changing a crank or cam sensor , it is best to check their readings with a multimeter . Voltage or ohms tests as per the repair manual can lead you in the right direction before removing the sensors. That said , do you have pressure at the fuel rail ? If the fuel pump is working well is there volts read on the positive side of the injector harness ? A noid light will quickly find that out for you. Not only do we need positive battery flow to injectors but the grounds are plied by the PCM so a noid light is best to test this while cranking. There are a slew of no start suggestions but we need to find out if fuel is getting through before attacking the ignition system which will involve PCM feedback from sensors as you've already attempted . No starts get us desperate for an answer and we submit by changing parts that sometimes yield success but only if that was the cause , a bad part. We always need to check parts if they're bad. A guy at a parts store always said to me long ago " was it properly diagnosed or are you assuming that's the cause ? " . Check spark plugs if they are wet . That will indicate fuel is getting through the injectors . That's a quick check if a noid light isn't available. If so , time to find out why there is no spark. Assuming the engine has not jumped timing and the crank position sensor is reading correct flywheel position and sensors is in fact reading , other sensors need checking as well . Cam sensor should be checked but is less likely to cause a no start than a crank sensor. O2 sensors , coolant temp sensors , idle air control , map sensors , etc. Are a long list of contributing parts that can cause a no start. This is why diagnostic trouble codes ( DTC ) should be sought. Cleaning grounds are a necessity as well. Some of the checks I've listed in this post have been made in other threads to the point they have been beaten to death but they always seem to return. Finding a no start cause sounds like a straight forward procedure but can be time consuming but also must be thorough until the cause or bad parts are found.
Im hoping this helps you but you are invited to search through threads pertains to this issue. I'm sure we've covered this before and expect to again. Please let us know what you find . Your always welcome to post and ask questions .
 
I'd check every fuse under the hood, particularly the ASD feed. Swap out the ASD relay with another and see if it helps.
 
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