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-   -   2005 WK Catalytic Converter Problems (http://www.jeepgarage.org/f5/2005-wk-catalytic-converter-problems-16821.html)

2005 WK 12-29-2010 12:23 PM

2005 WK Catalytic Converter Problems
 
Hey guys this is my first time posting on this site. i have a 2005 WK 4.7 V8 and its giving me codes for cylinder 1 misfire (P0301) and Catalytic efficiency below threshold bank 1 and 2 (P0420 and P0430). I have replaced my spark plugs 2 times already within the past 2 months because of the same problem with different cylinders. The code would go away for a few days then come back.

I was wondering if I am getting my cylinder misfire from bad catalytic converters? The Jeep does have 156,000 miles on it so I would think they need to be replaced. Any Opinions?

Also, I have been looking for replacement catalytic converters but cannot find anything for the 2005 4.7. Is it possible to use the converters for the 2005 3.7 or are they 2 different parts? Thanks for all the help.

2005JGC 12-29-2010 02:04 PM

Re: 2005 WK Catalytic Converter Problems
 
call up a dealer and ask them about the part number for the catalytic converter assembly for a 3.7 and 4.7, If they are the same or different you have your answer. Dont tell them what your trying to do because unfourtunatly some of them are lazy, being a tech I HATE being told "nope that wont work" even if I KNOW it will work, they are simply too lazy to look it up. So just ask for a partnumber for a 3.7 and then for a 4.7. You may also have luck at one of the online mopar parts stores.

ultimately misfires can be caused by alot of thtings not just sparkplugs, compression, poor fuel, burnt valve, head gasket, vacuum leak... the list goes on. One thing, if you didnt put the factory plugs in it that would be the first thing I did... the part number is on the emissions sticker under the hood near the gap spec.

a catalytic converter could cause misfires in severe instances but it would be more likely to misfire on an entire bank not just 1 cylinder.

what is most likely to happen is driving it on a misfire can and will melt down a catalytic converter by dumping raw fuel into the catalyst.

Scottina06 12-29-2010 02:23 PM

Re: 2005 WK Catalytic Converter Problems
 
do a search for a magnaflow cats....much cheaper...you will need a 2.5" or 2,75" inlet/outlet.

You could also have carbon build up in your combustion chambers. You can try seafoam or thee Mopar equiv. and clean the combsution chambers...especiaally with those amount of miles.

2005 WK 12-29-2010 07:38 PM

Re: 2005 WK Catalytic Converter Problems
 
Thanks a lot guys, I think my cats are bad, went to the mechanics today and the guy told me the inside is broken up and needs to be replaced and thats whats causing my misfire, Im just gonna look for the magnaflow cats cause theres no way I'm gonna pay $812 for factory cats then and additional $100-$200 to have them installed. Thanks for the quick responses guys, you really helped me out.

P.S. Hey Scott, I was curious about that sea foam cleaner, ive heard a lot about it but been scared to actually use it, how does it work exactly? where do I pour it? and how long will the car smoke for? After watching some video clip on people using im a little skeptical about using it. Thanks

Scottina06 12-29-2010 08:01 PM

Re: 2005 WK Catalytic Converter Problems
 
if your cat is busted...then that may be it. The seafoam or mopar equiv. has directions for use

2005 WK 12-29-2010 08:05 PM

Re: 2005 WK Catalytic Converter Problems
 
Thanks for all the help Scott, Ill try that seafoam tomorrow and see how that works.

Sam

2005JGC 12-30-2010 02:14 AM

Re: 2005 WK Catalytic Converter Problems
 
My .02... Repairing your cat issue is a place to start. But like I said, unless you have a P0300 and or P0301 P0303 P0305 and P0307, I REALLY dont see that causing your misfire. You have 2 exhaust manifolds (duh) and 8 cylinders (duh), so if exhaust back pressure is causing misfires naturally it would be on at least half or all of the cylinders (one or 2 cats plugged respectively).

Im not saying it for sure is not causing the misfire, but what I have seen, a cat will easily melt down with tons of O2 and HC's (misfires do this, oxygen and raw gas from non combusted gasses leaving the combustion chamber). But its pretty uncommon for a cat to cause a single misfire... I have never seen it personally (not that Ive been in the buisness for long).

Seafoam is good stuff, chrysler also has a "combustion chamber cleaner" that you can get in liquid for pressurized canister use and a Aerosol form which I have heard nothing but great stuff about, these would be basically the same thing as the seafoam. I have used seafoam in the past, not to repair anything but as a "maintainence" thing. I have seen misfires cured with combustion chamber cleaner, but obviously only if it is caused by something that the cleaner would clean.

ALSO, the 4.7 likes to collapse lifters and drop the rockers, Ive seen dropped valve seats on the 4.7 too. Is the misfire a dead hole, or just a slight miss?

2005 WK 12-30-2010 11:00 AM

Re: 2005 WK Catalytic Converter Problems
 
I understand that bad cats would cause at least half the cylinders to misfire, that does seem strange to me. I don't hear any strange noises coming from the engine so I hope the rockers and valve seats are still in place.

The misfire is nothing major, just a slight miss and the Jeep seems to be driving fine.

I guess I'll go back to the mechanics today and have him look into it some more, hopefully its nothing major and its a simple fix. Thanks for all the info.

Asativa 12-30-2010 11:34 AM

Re: 2005 WK Catalytic Converter Problems
 
Quote:

Originally Posted by 2005jgc (Post 325142)
my .02... Repairing your cat issue is a place to start. But like i said, unless you have a p0300 and or p0301 p0303 p0305 and p0307, i really dont see that causing your misfire. You have 2 exhaust manifolds (duh) and 8 cylinders (duh), so if exhaust back pressure is causing misfires naturally it would be on at least half or all of the cylinders (one or 2 cats plugged respectively).

Im not saying it for sure is not causing the misfire, but what i have seen, a cat will easily melt down with tons of o2 and hc's (misfires do this, oxygen and raw gas from non combusted gasses leaving the combustion chamber). But its pretty uncommon for a cat to cause a single misfire... I have never seen it personally (not that ive been in the buisness for long).

Seafoam is good stuff, chrysler also has a "combustion chamber cleaner" that you can get in liquid for pressurized canister use and a aerosol form which i have heard nothing but great stuff about, these would be basically the same thing as the seafoam. I have used seafoam in the past, not to repair anything but as a "maintainence" thing. I have seen misfires cured with combustion chamber cleaner, but obviously only if it is caused by something that the cleaner would clean.

Also, the 4.7 likes to collapse lifters and drop the rockers, ive seen dropped valve seats on the 4.7 too. Is the misfire a dead hole, or just a slight miss?

i second this opinion, couldnt have said it better myself! Ive never seen a failed/failing converter cause a misfire, and ive been working on cars professionally for 11 yrs now. MY STRONG ADVISE IS TO FIND A TECH THAT CAN SOLVE YOUR MISFIRE CONDITION BEFORE INSTALLING NEW CONVERTERS

sanitarium16 12-31-2010 11:13 AM

Re: 2005 WK Catalytic Converter Problems
 
isnt there a federal warranty on cats?

xj31 12-31-2010 12:10 PM

Re: 2005 WK Catalytic Converter Problems
 
Quote:

Originally Posted by sanitarium16 (Post 325744)
isnt there a federal warranty on cats?

Yea but it's 8 years 80,000 miles

edwardalmost 01-22-2011 02:33 PM

Re: 2005 WK Catalytic Converter Problems
 
re: magnaflow dual exhaust
Quote:

Posted by trucker - Gibson exhaust is dedicated to the truck, SUV, van, and motorhome market. Gibson exhaust systems provide that mean, burbling, deep exhaust note that lets everyone know what you've got under the hood of your truck. And the free-flowing design inherent in every Gibson exhaust product actually increases power and torque on your vehicle. Available with aluminized or stainless-steel construction, Gibson exhaust provides several different system configurations.
Is the magnaflow still for sale?


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