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Wont start, not fuel pump, possible crank sensor???

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Old 07-15-2011, 05:28 PM
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Default Wont start, not fuel pump, possible crank sensor???

It's cranking but won't start. Please help. Thanks.
Old 07-15-2011, 05:47 PM
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Got spark?
Old 07-15-2011, 06:03 PM
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I haven't checked that yet. Its got new plugs and wires that I put in last month. That's one thing I'm gonna check tho. Can anyone tell me where the crank sensor is on a 1990 xj? 4.0l
Old 07-15-2011, 06:42 PM
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How are you sure it isn't fuel related?
Old 07-15-2011, 06:48 PM
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#1 thing to do is to pull a plug, place the plug electrode near a good engine ground, and have a buddy crank the engine while you watch.

You are looking for a strong, BLUE, snapping spark. Yellow/orange/white spark is a weak spark, which may not be strong enough to start the engine.

Start there. Test your way to a solution.

Do you hear the fuel pump energize and run for about 2 seconds when the key is turned to the ON position?
Old 07-15-2011, 06:50 PM
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I pulled the fuel pump that I just replaced a month ago and it was still pumping but I took it back to the parts store and got a replacement an put it in last night. Nothing happened. Ugh this sux. I just moved to van Buren Arkansas from Joplin las Sunday and then it does this! Fml
Old 07-15-2011, 06:55 PM
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You could kill two birds with one stone and just pour some gas in the throttle body. If it starts its fuel if it doesn't its spark.
Old 07-15-2011, 07:08 PM
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Originally Posted by tjwalker
#1 thing to do is to pull a plug, place the plug electrode near a good engine ground, and have a buddy crank the engine while you watch.

You are looking for a strong, BLUE, snapping spark. Yellow/orange/white spark is a weak spark, which may not be strong enough to start the engine.

Start there. Test your way to a solution.

Do you hear the fuel pump energize and run for about 2 seconds when the key is turned to the ON position?
Yeah that's what I'm figuring. I gotta get a buddy to help lol.
Old 07-15-2011, 07:14 PM
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No need for a buddy if you just pour some gas in the t.b. really sounds like fuel. Do you smell gas when you crank for a while? I just hate checking spark that way. Only do that last cause coils don't go out allll that often.... plus I don't like getting shocked.... does happen.
Old 07-15-2011, 07:28 PM
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Yeah I don't wanna get zapped either. I think I'm gonna go bar hopping tonight then worry bout testing tomorrow. I hear the crank sensors go out often aswell. But I bought one just in case, 30.99 won't break me so I'll look at changing this. Anyone know how hard it is and where exatly it is??
Old 07-15-2011, 07:34 PM
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Right on top of the flywheel housing lol... Driver's side
Old 07-15-2011, 07:42 PM
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Sort of a pita to get at.... you have small hands??
Old 07-15-2011, 07:48 PM
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Lol. I got skinny hands but not real small. Anyone got any pics. It's a 1990. Thanks
Old 07-15-2011, 07:52 PM
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Originally Posted by 90xjcjf
Lol. I got skinny hands but not real small. Anyone got any pics. It's a 1990. Thanks
Hang tight I think..... this might help http://www.lunghd.com/Tech_Articles/...iagnostics.htm
Old 07-15-2011, 07:53 PM
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Originally Posted by Slick761

Hang tight I think.....
Awesome


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