rlh23

On that note, could the O2 extenders I have be causing the issue? Would it make sense to have extenders in both locations (pre-cat and post cat)?

ALEV8

New cats on yesterday. CEL today. P2197.

rlh23

Time for a Group Buy on an ECU tune!

ALEV8

Agree! Durametric cleared the code after a few tries. Have not yet come back. For sure mine are twisted....and possibly causing the P2197 error. I also did not tighten the 02 sensors more than 15-20ft/lb. Maybe it could have vibrated loose on bank 2. The Magnaflow replacement cat also has a threaded bung for a SMALL diameter threaded something, 3/16" or so in diameter. needs to be plugged up I guess with a bolt.

DC911S

You have been running it with an open hole in it? small as it is? I'm guessing its a hole for a thermocouple to measure exhaust gas temp. mmmm yes, it needs to plugged and sealed properly.

ALEV8

It's gotta be that hole directly opposite of the bank 2 cat sensor 1. I still don't get why Magnaflow would design that other than cross compatibility with other platforms. Plug the hole I will.

DC911S

Use a copper washer with a bolt.

ALEV8

Pro tip! Thanks!

ChicagoSpeed996

Something isn't making sense. You guys are getting a pre-cat O2 sensor code. Changing out catalytic converters will not help from the information the computer is telling us. All the issue is before the cats. The fuel adjustment is done from information from the MAF, the O2 sensors (only the ones upstream of the cats) and the coolant/intake temp sensors. So it is either a header gasket leak, or the O2 sensors are bad. Other than that, I could be something totally different with the engine. So things to double and triple check,
1. The blue sensors are towards the engine, gray wore O2 after cats.
2. Switch the connectors in the engine bay and see if that helps (bet this is the issue). Swap them.
3. Exhaust leaks at the header gasket.

ChicagoSpeed996

No, the upstreams need to be in the exhaust flow.

ChicagoSpeed996

Or the last posssibilty is that you really are running lean at the limits of the engine adjustment capabilities and need a tune.

German888

I ordered 2 new upstream sensors. In my case I hadn't experienced the CEL until replacing the OE cats with the Top Gear group buy 200 cell's. Points me in the direction of bad up stream sensors or the possibility of being damaged during the install? I wasn't particularly careful with them and may have stretched a wire or contaminated the tip.

Please pardon my ignorant comment about trying upstream spacers. That's obviously not a correct option. I'm getting desperate.

If the the new sensors don't fix it I'm headed toward a tune although I'm only 2 months away from a 4.0 conversion and It would seem a waste of funds since the builder will likely be adding a completely new tune at that time.

ALEV8

Temporary fix with a Holley carb stud.....

lowbee

I would try putting the OEM CAT pipes back to make sure everything still works before I try ripping everything else apart if you have no CEL before Topgear...

ALEV8

Just for clarity's sake my upstream sensors are brand new basically and I replaced one cat, not both. I sent the other back for a refund and will get another OE exact replacement from Magnaflow. It's worth the extra $200 and fit and appearance is better. Only bank 2 side needed replacing immediately.

FWIW I also put a container of HEET into the gas tank to rule out crappy gas. $3 checks that box.