Rear 02 sensors???

[AR]

Can anyone point me in the right direction as to where to find the function for this in a trottle by cable car ( 1994 NSX-R ).

I am planning to install hi flow cats, but all of the ones that I've seen are " bung less". Will it be OK to just delete them and leave the two in the headers.

Cheers,

AR

 

[AR]

Any ideas people? I have the day off tomorrow and want to have a weekend at it, but not at the expense of the car's efficiency.

Cheers,

AR

 

[Daedalus]

I don't know how similar that vehicle is to US vehicles. In the US the absence of the rear O2s will cause a CEL, but will not degrade performance. There are O2 simulators that are made to replace the O2s to keep from triggering the CEL. There's no source for NSX-R manuals in the UK?

 

[AR]

Thanks for that mate, so it is safe to assume that just like in the OBD2 they monitor the system, but do not affect performance. My car is one of 2 NA1 NSX-R in the UK, not even the Honda Tech could come up with a reason for them to be there, and not a chance of a technical manual.

Cheers,

AR

 

[Daedalus]

I couldn't make that assumption, but I also doubt it would cause any damage if you unplugged them. If performance suffers you can then buy simulators. Keep the old cats around just in case the simulators don't fool the ECU either. I'm curious to whether your car has a standard OBDII connector or not. It's not a small feat that Honda had OBDII on cars in the US a full year before it was required. Having it on a '94 would have been even more of a challenge.

 

[cbrdspeedfactory]

when you are dealing with a nice car like the nsx,

it is worth the extra 30 bucks to buy two bungs with allen cap plugs (can be purchased in stainless or mild steel) and put two o2 extenders (spark plug foulers) in them to keep from getting the code.

It's a cheap fix, and having them tig'd or mig'd into your pipes shouldnt cost more than 45 bucks.

cheers

cb
cbrdspeedfactory.com

 

[Larry Bastanza]

If the car is pre-OBDII (1994 US models are NOT OBDII) there is only one 02 sensor per bank. In this case "rear" means the rear bank 02 sensor on the engine (Cylinder 1,2,3).

With one 02 sensor per bank, hi flow cats are just bolts on, with no side effects.

HTH,
LarryB

 

[AR]

If the car is pre-OBDII (1994 US models are NOT OBDII) there is only one 02 sensor per bank. In this case "rear" means the rear bank 02 sensor on the engine (Cylinder 1,2,3).

With one 02 sensor per bank, hi flow cats are just bolts on, with no side effects.

HTH,
LarryB

Larry yet my car has the 2 Lamda Sensors ( front) and the 2 rear sensors.

Here is a picture of the cat:


So this is an OBDI with OBDII Cats???

Any ideas?

This is an NSX-R BTW if that helps.

Cheers for any help in clarifying this.

AR

 

[Larry Bastanza]

This is very different compared with the US models. I am thinking this is the secondary 02 sensor, in an OBDII system. You need to check this for sure. Look under the glove box door on the lower glove box panel and see if you have a plastic cover that has the OBDII connector behind it.

I am not sure in your location you would have the same system as we do in the US. With that said, assuming it is an OBDII type system, removing these will set a few codes and put your engine check light on.

So you need a way to install them at least close to where they are now. I have a 1995 here now and the cats, although they have the second 02 sensor, they are very different from the mounting persepctive. Your front cat in the pic looks like a US 1994, but we do not have the bung.

I hope this helps.

Regards,
LarryB

 

[AR]

Here is a shot of the connectors in the trunk, the bright lines are the O2 cables sheating that is also used to ground them. Sorry about the poor picture. Is the OBDII port in the fuse box?

Cheers,

AR

 

[Larry Bastanza]

Is the OBDII port in the fuse box?

Cheers,

AR

Look under the glove box door on the lower glove box panel and see if you have a plastic cover that has the OBDII connector behind it.


HTH,
LarryB

 

[AR]

Larry I had a look this morning, all I could find was a little panel on the passenger footwell for the fuses. No connector for diagnostics there. I looked by the drivers side just in case, nothing there either.

Cheers,

AR