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Bishie336 10-21-2013 04:59 AM

cranks and sputters.
Hi,My 4.0 l6 sputters when i attempt to start and cuts off instantly.It started with Intermittent Crank sensor and injector 1 fault codes.It then died completely. I changed the injectors with upgraded 4 hole type and CPK.It jst didnt work.Now the fault codes cant disply coz I had removed the battery terminals.
I realy dnt knw what to do.Can someone assist

Duh 10-21-2013 05:22 AM

Check fuel pressure. Sputtering often means low fuel into cylinders.

new2site 10-21-2013 01:22 PM

Your battery's voltage is quite possibly should test at 12.6 resting voltage (not running). These WJ PCM's demand top rate voltage...if it's even on a low side they'll do what yours is doing --engine will crank...but when started will just sputter out. If you have access to another battery from other vehicle with close cranking amp rating give it a shot...don't shut hood while testing this as WJ's have very little clearance between battery and hood (in case test battery is on "tall side")

Post back follow up results..

cykaaro 10-21-2013 01:29 PM

While in there worth cleaning the battery connectors, ground from battery on the engine side, and engine to firewall. This will just know you're getting a good connection and isn't part of the problem.

new2site 10-22-2013 12:15 PM


Bishie336 10-30-2013 12:57 AM

Thanks for your tip guys.I will try them out.I noticed one more thing though.The NGK spark plugs (#ZFR5N) currently fitted have a gap of 0.90 as opposed to the recommended Champion spark plugs (#RC12ECC- copper plus) which has a gap of 0.36.Could this be contributing to the problem?

ChrisHager 10-30-2013 08:34 AM

2 Attachment(s)
Woah! Definitely re-gap them!

rdkendrick 10-30-2013 01:02 PM


The plugs may be cleaned using commercially available spark plug cleaning equipment. After cleaning, file center electrode flat with a small point file or jewelers file before adjusting gap. The Gap specification is 0.035 for the 4.0L engine, and 0.040 for the 4.7L engine.

CAUTION: Never use a motorized wire wheel brush to clean spark plugs. Metallic deposits will remain on spark plug insulator and will cause plug misfire.

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Jeepforthewin 10-30-2013 02:27 PM


Originally Posted by ChrisHager (Post 17285594)
Woah! Definitely re-gap them!

X2!! Gap plays a pretty big role!

The time now is 04:57 AM.

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