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2005 Jeep Grand Cherokee - 5.7L Hemi Code P0420

Posted: Mon Dec 14, 2009 4:52 pm
by RON169
I HAVE AN 05 JEEP GRAND CHEROKEE LIMITED THAT IS DRIVING ME CRAZY.

THANK YOU FOR ALL YOUR HELP BUT THE CUSTOMER PULLED THE CAR.I WAS LOOKING FORWARD TO SOLVE THIS ONE.THANKS RON.

Re: 2005 Jeep Grand Cherokee - 5.7L Hemi Code P0420

Posted: Tue Dec 15, 2009 5:14 am
by JBUTITTA
Sounds like you may have a bad catalytic converter and torque converter (not uncommon on this vehicle). jerry

Re: 2005 Jeep Grand Cherokee - 5.7L Hemi Code P0420

Posted: Tue Dec 15, 2009 7:00 am
by brianp87
Both issues are seperate test the cat

Re: 2005 Jeep Grand Cherokee - 5.7L Hemi Code P0420

Posted: Wed Dec 16, 2009 3:26 am
by steven kiser
welcome to the forum. using the scanner check the balance between the front and rear 02's.if it's close replace the cat. i also use the rattle test. when the exhaust is cold shale it. if it rattles the cat's junk. i use an infrared temp gun to check the cat. it sounds like a converter issue. i suggest you only use o.e.m.

Re: 2005 Jeep Grand Cherokee - 5.7L Hemi Code P0420

Posted: Wed Dec 16, 2009 5:38 am
by Tim Martin
at that kind of mileage, the cat is out a business. The cat monitor should be about 1/2 of the front o2 sensor.