What options in regards to cat replace or delete ?

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Limey
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What options in regards to cat replace or delete ?

Postby Limey » Mon Aug 22, 2022 6:58 am

I think one of my cats are plugging up , I occasionally smell sulphur type smell and think some power loss is present.
I don’t live in a state that has emissions testing. What would be the most cost effective ways to either A replace cats or B delete then completely. ? Thanks.


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VStar650CL
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Re: What options in regards to cat replace or delete ?

Postby VStar650CL » Mon Aug 22, 2022 7:46 am

If it isn't throwing codes then most likely it's one of the rear converters going bad, you can replace those with a straight pipe with no issues at all. Front cats are more complicated because you need to either install emulators to fool the ECM into thinking the rear O2's are still present, or get an ECM tune so the ECM quits looking for them. First thing I'd do is find out which cat is making the stink. Warm the engine completely with a highway run, then aim an IR thermometer at each cat. They should all be substantially hotter at the outlet than the inlet. One that's less than +30F or so is dying, one that's the same temp or cooler at the outlet is completely dead.

Limey
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Re: What options in regards to cat replace or delete ?

Postby Limey » Mon Aug 22, 2022 7:06 pm

No codes are present except for bank 1 or 2 oxygen sensor error. I need to double check .

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VStar650CL
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Re: What options in regards to cat replace or delete ?

Postby VStar650CL » Tue Aug 23, 2022 5:09 am

If the codes are P0420 or P0430, that's usually a bad cat and not a bad sensor.

Limey
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Re: What options in regards to cat replace or delete ?

Postby Limey » Tue Aug 23, 2022 5:38 am

VStar650CL wrote:
Tue Aug 23, 2022 5:09 am
If the codes are P0420 or P0430, that's usually a bad cat and not a bad sensor.
No, it wasn’t one of those codes. I’ll check to get specifics later.

So am I right in thinking that if one of the further down cats are going bad I wouldn’t necessarily get an error code ?

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VStar650CL
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Re: What options in regards to cat replace or delete ?

Postby VStar650CL » Tue Aug 23, 2022 6:54 am

Yes. The rear cats aren't monitored, only the fronts. That's why the rears can be eliminated without jumping through any technical hoops.


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