Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: Bubba on June 02, 2015, 06:36:34 PM

Title: sputtering when hot
Post by: Bubba on June 02, 2015, 06:36:34 PM
norm the rescue zj seems to be having an issue with a general lack of power that seems to get worse the longer the journey and some sputtering when hot when you boot it  it mimics o2 sensor problem but no codes
i am thinking its the cat as it does rattle anyhoo  any other ideas before i buy a cheap cat ? 

on ebay i see there are some cheap cats that say unapproved and approved ones any one know  what thats about

performance from cold is ok but does seem down to my memory of others but as exhaust gets hotter does seem to drop of and there is a hot scorchy smell when you park up and switch off
Title: Re: sputtering when hot
Post by: bgbazz on June 02, 2015, 07:39:37 PM
Sounds like a coil problem to me....had these symptoms on an AMC in the past. Finger tip test will confirm.
Title: Re: sputtering when hot
Post by: Dave69 on June 03, 2015, 06:29:59 AM
the cheap cats are not built to the same standards as the branded equivalent. found that out when my toyota failed on emissions, tried a new cat which improved but didn't meet requirements (new O2 sensor as well) borrowed another branded cat and lashed into place which then improved but the cost outweighed the value of the car so wasn't worth the cost of a replacement
Title: Re: sputtering when hot
Post by: LairdScooby on June 15, 2015, 01:16:37 AM
The big thing about "Type Approved" cats is they must be used as replacements on 2001 and later vehicles.

If the vehicle was registered before 2001 a non-type approved cat aka a cheapie can be used as a replacement cat. Down to some EU law i believe. That's the basics anyway, there's a bit more to it than that but can't remember just now.

Your problem does indeed sound either like a coil or perhaps either a cat or fuel pump relay problem (dry solder joints inside the relay) or possibly something simple like a blocked fuel filter.
Title: Re: sputtering when hot
Post by: Bubba on June 18, 2015, 03:19:25 PM
used the drain rod method on the cat no problems since
Title: Re: sputtering when hot
Post by: JamesH on June 18, 2015, 04:17:42 PM
 :greggmo: Good work  :icon_winkle: Probably sounds a bit better too
Title: Re: sputtering when hot
Post by: LairdScooby on June 18, 2015, 07:57:37 PM
used the drain rod method on the cat no problems since

Excellent! Still looks like a cat so as long as the emissions are ok for the MoT there's no reason to change it. I run decats on my little fleet, saves a fortune in fuel, goes and sounds lots better too!
Title: Re: sputtering when hot
Post by: Bubba on June 19, 2015, 07:21:27 AM
does not sound as good as the 5.2 zj though
Title: Re: sputtering when hot
Post by: LairdScooby on June 19, 2015, 10:19:32 AM
does not sound as good as the 5.2 zj though

There's something about the sound of a V8 you just don't get with other engines. I would have loved a V8 but couldn't justify the extra costs - maybe next time!