VY V6 commodore 2.5inch exhaust o2 sensor problems

[Scrotty06]

So long story short my Stock exhaust didn’t set off my o2 sensors after I put a Redback 2.5inch cat back system on it the o2 sensors went off after I cruise at 100 for about 5 minutes and then it guzzles fuel like no tomorrow. So I’m just wondering what I can do to fix the o2 sensors and no I don’t wanna put my stock exhaust back on untill I’ve tried everything to get this redback exhaust to work. Has anyone had similar issues with the Ecos putting an aftermarket exhaust on and having o2 sensors play up?

 

[Fu Manchu]

Check for leaks at the manifold. Check for a cracked manifold.

 

[Scrotty06]

Check for leaks at the manifold. Check for a cracked manifold.

I’ve checked for leaks it was fine when it had the stock exhaust on it o2 sensors never played up even after driving 200+ kms home after I brought it it’s just recently when I put the new exhaust on I’m thinking it might have been the ceramic coating in the exhaust or there’s just too much flow going through the exhaust now

 

[Fu Manchu]

You’re missing something here.
You’re assuming there are no leaks.

You’ve just been reefing on the exhaust and wiggling it around. Maybe banging bits with a hammer. Before and after are very different.

Leaks are found by using a smoker/automotive smoke machine to fill the exhaust. Where ever the smoke comes out is your leak. This is a benchmark test. You may need a laser pointer or torch to find the smoke. Where the torch fails, the laser wins.

We use a smoker on the intake side as well. That will make every single tiny leak become highly apparent. Every hard hose, every damaged gasket.

This is unlikely to be resolved by loading the parts cannon and firing parts and guesses. You need data. You need evidence. Dismissing things with guesses and assumptions is no way to resolve the problem unless you get lucky.

 

[Fu Manchu]

It’s not the ceramic coating any more than it’s the humidity or the neighbours dog barking.

 

[Scrotty06]

You’re missing something here.
You’re assuming there are no leaks.

You’ve just been reefing on the exhaust and wiggling it around. Maybe banging bits with a hammer. Before and after are very different.

Leaks are found by using a smoker/automotive smoke machine to fill the exhaust. Where ever the smoke comes out is your leak. This is a benchmark test. You may need a laser pointer or torch to find the smoke. Where the torch fails, the laser wins.

We use a smoker on the intake side as well. That will make every single tiny leak become highly apparent. Every hard hose, every damaged gasket.

This is unlikely to be resolved by loading the parts cannon and firing parts and guesses. You need data. You need evidence. Dismissing things with guesses and assumptions is no way to resolve the problem unless you get lucky.

I work in a very old school workshop so I don’t think we have a smoker but I’m not gonna chase tiny little leaks because then I’ll want to fix them all I’ll get under the Ute tomorrow and spray some soapy water on the exhaust fittings and see what’s going on because I should’ve checked it when I installed it. I didn’t put the new gasket in where the flange goes so I think that also could be my issue too. Cut corners, pay the price I guess

 

[Fu Manchu]

So you don’t want to find air getting in and throwing out the o2 data but you do want to fix this issue by guessing.

Ok.

 

[Scrotty06]

So you don’t want to find air getting in and throwing out the o2 data but you do want to fix this issue by guessing.

Ok.

Hey like I said my o2 sensors were completely fine before the new exhaust got put on it’s got something to do with the exhaust and it’s a cat back system so I haven’t touched the sensors or the headers or the cat so I’ve ruled all of that out as an issue ‍