o2 sensor trouble w/ high flow catalytic converter

I've recently added a zz performace 3" downpipe with high flow cat.,copper spark plugs 606's I believe, 180 thermo., and 3.6 mps. Two days after, my rear o2 sensor went off. I think it was 1040 code. not sure . should I replace the sensor or assume it 's my mods.

High flow cats are well known for triggering rear O2 sensor codes. They sell a rear O2 'sim' that should make the code go away, or someone with a tuner can disable the rear O2 code.

I guess it depends on the cat more than anything. I never had a code thrown from the cat that came with my RT downpipe. I'm still using that cat, even though I went to headers, without a rear O2 code ever being thrown.

rear O2 doesnt effect any performance, so you can either delete the code with a scanner, or buy an O2 sim(essentially the same thing)
i never had the cat code come on except on long highway trips, and i had no cat at all! i guess some cars are more finicky than others.

on another note, 606 plugs are probably too hot for your mods.

_________________
1996 with 254k miles, L32 4" FWI -> ported N* -> Ported Gen V w/3.0" Pulley, Stage 3 Phenolic I/C, ZZP FMHE, 1.84 RR, Headers and 3" pipe to mufflers, F-body brakes, and lowered on Eibachs. -RIP
AMG C400 White on black. Stage 2 w/E30 - 11.9@117 -daily
o2 sensor trouble w/ high flow catalytic converter Dsc_0110

o2 sensor trouble w/ high flow catalytic converter Dsc_0110

606 plugs are for a Stock application. You should be running AL605's for sure, maybe even 104's. Who makes ZZP's HF cat? I got mine(Magnaflow) from Hogan Performance, it's OBD II compliant, has never thrown a code.

I thought the O2 sims were illegal now? Can you still buy them?

The simulator is just a resister from what I know. If you can find the value, could make one from Radio Shack parts for cheap. I'm sure someone in the 3800 community has done this. Please tune in if you know...

DON'T replace the sensor. This will NOT solve your problem!

_________________
'05 GTO 6.0L • 6-spd • 95k miles • 0-60: 4.8s • 16.9 avg MPG • Nelson Ledges Lap: 1:26

'95 Celica GT 2.2L • 5-spd • 165k miles • 0-60: yes

'98 SC Riviera • 281k miles • 298 HP/370 TQ • 0-60: 5.79s • ET: 13.97 @ 99.28 • 4087 lb • 20.1 avg MPG • Nelson Ledges Lap: 1:30
3.4" pulley • AL104 plugs • 180º t-stat • FWI w/K&N • 1.9:1 rockers • OR pushrods • LS6 valve springs • SLP headers • ZZP fuel rails
KYB GR2 struts • MaxAir shocks • Addco sway bars • UMI bushings • GM STB • Enkei 18" EV5s w/ Dunlop DZ101s • F-body calipers
EBC bluestuff/Hawk HP plus • SS lines • Brembo slotted discs • DHP tuned • Aeroforce • Hidden Hitch
^^^ SOLD ^^^ frown

'70 Ninety-Eight Holiday Coupe 455cid • 116k miles
^^^ SOLD ^^^ frown

1998 Riv wrote:: 606 plugs are for a Stock application. You should be running AL605's for sure, maybe even 104's.

I'd have to agree here.
I am running 104's right now, and put them in before any other mods. I pulled a couple of plugs a few weeks ago (~3000 miles on plugs - just a gutted air box) and they looked great, plus the gaps were right where I set them (only 3000 miles on them of coarse).

Thanks for the information on the Hi-Flow Cats.