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Cylinder 6 not fire

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Old 09-03-2011, 01:37 PM
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Ok my Cherokee cylinder 6 does nthin I unplug the injector connection playen around today and it didn't change the way it was running it should have drop the idle and started whacking but it didn't why is this

Last edited by 98cherokeeguy; 09-03-2011 at 01:40 PM.
Old 09-03-2011, 07:44 PM
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Did you check pulse to the injector? Make sure its getting signal. If it is, the injector may be bad. Check compression also. Let us know what happens......
Old 09-04-2011, 05:34 AM
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Do you have a check engine light or any trouble code? Any actual symptoms that brought you to playing around with this injector?

Agree with above advice.

First, Use a "noid light" to check for injector pulse to that fuel injector.

Be sure injector, plug, plug wire, distributor cap are working properly.

A compression test is never a bad idea in the event that something internal is going on.
Old 09-04-2011, 08:44 PM
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Ok compression was around 130 on all cylinders
And the injector sometimes works and doesn't
What made me play around with it was the fact that sometimes she ran perfect and otheres she wouldn't
Old 09-05-2011, 12:55 PM
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Ok the easiest way to check the injector is swap it with another one. If the miss moves, your injector is bad. If it don't move then you have a electical problem. First I would clean the plug...and throw some Dielectric grease in there....see what happens. But the good news is your 3/4 into fixing it. Diagnosis is the most important. ...
Old 09-05-2011, 01:35 PM
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Had the same problem. Ended up being melted injector harness between cylinders 5 & 6.
Old 09-05-2011, 06:15 PM
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Alright I check my wires and they are all good havnt swap the injectors but thinking it's a bad injector but gunna try swapping them first and apperciate the help
I was previously running on 3 cylinders but got her fixed up so far it's just number 6 is bipolar haha
Old 10-28-2011, 12:36 AM
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Alright guys I'm bringing this bad up cause I've done a tune up and replaced all injectors with new ones and its still misfireing need help its all apperciated
Old 10-28-2011, 12:47 AM
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swap coil boots....presuming that is the ignition system you have.
if problem moves bad booty ( i didn't say that did i?).

hmmmm. check , i mean ohm out plug wires? pull plug six, does it have oil on it? is it gapped right?

smell like gas?

just stuff to check sir!

cpnwrench

Old 10-28-2011, 01:31 AM
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Check it again at higher speed. If it's a vacuum leak affecting that cylinder will have power above idle.

Check the spark to it - hold the wire above ground -- it should be a crispy thin BLUE spark at least 1/2" long. Good way to test the plug wire. Ohm test won't always detect a bad plug wire.

Swap the plug with another cylinder - if problem moves ---.

On some the EGR Valve is back there, make sure it's closing all the way.
Old 10-28-2011, 05:33 AM
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Did your tuneup include new plug wire, plug, distributor cap?

There is no EGR valve on a 98 4.0 engine.
Old 10-28-2011, 07:17 AM
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I have a dis. And I've replaced the on coil twice and what an egr valve
The spark plugs are gapt right and the old ones burnt good they where a little dark like unburnt fuel and good an intake leak and exhaust leak cause this
Old 10-28-2011, 07:20 AM
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Ya I did everythang cap,rotor,wires and plugs and my coil as well too
Could it be my dist cause I have been seeing really low oil pressure
Old 10-28-2011, 10:05 AM
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Try post #10 - or you can spend a fortune throwing parts at it.

Intelligence always overpowers brute force.
Old 10-28-2011, 01:07 PM
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Thangs is I've tryed it all but a vaccum leak


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