V8V Running Rich or Bad O2 Sensors
 

Ran the diagnostic. Looks like an O2 sensor issue.

Under mid throttle yesterday there was a one second drop in power / hesitation.

What is a common issue with rich condition on these cars?

Error 4/4 - P2198 Generic O2 Sensor Signal Stuck Rich Bank 2 Sensor 1
Error 3/4 - PO153 Generic O2 Circuit Slow Response (Bank 2 Sensor 1)
Error 2/4 - P0153 Generic O2 Curcuit Slow Response (Bank 2 Sensor 1) *SAME AS ERROR 3/4 (I find this odd...)
Error 1/4 - P0133 Generic O2 Circuit Slow Response (Bank 1 Sensor 1)

Would you change your plugs given the rich condition (perhaps they are partially fouled).

Do you have a sport catalyst?

The V8V has a good knock detection system, which will detect if there was a misfire. If the engine was running rich and the plugs were the reason..you would have at least a P0300: Random Misfire, which then I would say to replace the plugs as a first step...only way I see you would not get the misfire code store is if your Misfire Corrections are not learnt, that could be a case and you could be casing this tail for awhile untill learnt, to learn the corrections you need to take it to the dealer to see if there stored and to do a relearn if needed..get print outs as proof

With Bank 2 upstream sensor stuck rich, doesn't mean you are rich..but could also mean you are running rich(one of those 50-50). At this point you would need to datalog the upstream sensors and force a air leak to see the reaction.

If there is no reaction to the Bank 2 upstream after warmed up, I would swap the upstream sensor sides and see go from there..

With the slow response of the sensors, you could also have a exhaust leak at the catalysts, but I see this storing faults for the downstream sensors..

If you clear all the faults and drive to complete the drive cycle, do you get the same 3 faults.. P2198/P0133/P0153??

No aftermarket cats. All stock 2006.

Are the upstream sensors easy to access underbody?

I've cleared the code and driven 50 km. How many km is a complete drive cycle?

IIRC correctly from Irish's previous instructions to me, to properly attempt a (blind) misfire relearn, you need to find a long straight a relatively deserted stretch of road (with no stop signs or lights).

Get the car into 6th, AC off, and take it from 45 kph to 110, then release the throttle and have it settle back below 45 kph on its own. Then repeat, at least once (more if you can, and any stop or braking or turning beyond 10 degrees will abort it). If you have the tools that the AM techs have you can tell whether the relearn has 'caught'. But without them you are just left to see whether further symptoms occur.

I noticed some stalls recently (would happen with a brief coast after engaging the clutch, foot off the gas) after my ECU upgrade (but also after my track day) and apparently the misfire corrections can be lost after an ECU upload. As a first step before bringing it to the dealer I tried the blind relearn procedure. So far so good, no stalls but I haven't put tons of miles on it.

V8vs always run super rich, this will always cause premature catalytic & 02 sensor failure compar to other cars. It's probably 02 sensors but one of your ats could have failed as well. Only way to cure the problem is upgrade cats and get the ECU upgrade to lean out the car significantly.

Yes, all is done from under the vehicle..prefered on a lift versus jack stands. You will have to drop the center exhaust section, unbolt after cats and at rear muffler..then just let the swing and hang the center section there..disconnect the O2 sensor connectors (blue and grey connectors secured on black bracket near end of exhaust header flange) drop the cats by removing 3x nuts each side..then swap the upstream sensors and refit all back. Again prefered would be to datalog the reading first before going this step..
You could very well have a air leak which is causing vehicle to rich out the fuel trim..in most cases, the rule is when rich codes are stored, system is getting to much air, it's very rare I've seen to high(above spec) of a fuel pressure to force system rich(1% is cars that have been played with the tune)..99% of cases are air leak, system is suching in air after the throttle, which is unmetered causing system to rich mixture..

Am I able to datalog with a top shelf OBD tool from my local auto shop? I picked one up for $350 but plan on returning it now that I continue to get the same codes...

I did the noted 6th gear 45 kph to 110 kph to relearn. Emission error and CEL immediately came back on.

Following codes were thrown:
-P0153 O2 Circuit Slow Response (Bank 2, Sensor 1)
-P0133 O2 Circuit Slow Response (Bank 1, Sensor 1)
-P0153 (twice which is odd...) O2 Circuit Slow Response (Bank 2, Sensor 1)

Note - I didn't get P2198 Generic O2 Sensor Signal Stuck Rich Bank 2 Sensor 1 this time...

When started cold there is definitely some hesitation. I pulled fuse 22 and when gently accelerating in 1st or 2nd to 3000 rpm and shifting up a gear, the exhaust pops when the revs drop to 2000 rpm (it sounds good!)

Where is the most likely place for an air leak in the intake system? Perhaps bubble / soap test?

Come to think of it, I remember something being sent out about P0153 and P0133 stored together..but to get info the vehicles log file had to be sent to the hotline. My best bed would be to check first with your local dealer and get them to send in your log file to there district manager(could be a simple update, or chafed wire that is known about)..I have no clue what the issue is they know about nor could I find out with out the log file(dealers AMDS records the log when plugged into your car)..

You could try and use a off the self scanner to data log, but most will not do this function, or are limited when using on exotic cars(even Snap-On units which are 3,000-6,000$)

I’m told the most likely cause is the upstream oxygen sensor. Also it’s been recommended to check for air leaks around the trunking/throttle bodies.

Guys I wondering is it worth buying the diagnostic tool that gives you the codes? My emssion service just came on ans Im guessing its the O2 sensor. Im not sure if its worth just taking it to the dealer or buying one those machines?

08 V8V

I'm having this exact same issue after my remap; stalls and what has been described as misfires (frequent erratic breif power losses, feels jerkish). Strangely restoring the OE mapping clears this up. Was told a few days ago about the re-learn procedure but my challenge is finding a place to do it. You're in Toronto as well I see, where abouts would you recommend?

I'm in downtown Montreal area and do this in about 1hr.. I do this on the trans canada, get up to 110kph just before an exit, take the exit and coast to 35kph on the service..takes 2-3 times for the AMDS to flag the car as "learned"..so without a AMDS I'd say do it 4 times and you should be gold..

Tough to find a place around here to do more than 2 or 3 consecutive runs I found. I took mine up the 404 to around Bloomington after dark and hit some of the north/south roads (Warden, Kennedy, McCowan etc). There's little traffic and the limit is 80 km/h so you can get away w it but you can get unlucky and hit a light and mess up the run. The other possibility would be a late night run on the 407 which is 8-10 lanes in places and if you throw your hazards on and stick in the right lane, you might be able to do a few in a row. I just have an allergy to that place as I abhor toll roads.

I've actually been experiencing similar issues lately and a kind of perplexed as to why. They antedated my most recent ECU upload (version 2 from Stuart and the boys) so I'm wondering if perhaps the runs I did a couple months back did not successfully trigger a relearn or if perhaps it's another problem.

Issue 1: I notice a fall off/hesitation in power when accelerating through ~60 km/h in 2nd or 3rd. Issue 2: repeated stalls when the car is hot (been driving for at least an hour or two) generally when I shove in the clutch and hold it down w my foot off the gas. This happens irrespective of the amt of gas in the tank. Not sure if the two are related or not. Certainly the stalls did not happen before I did my first ECU upload. But I recognize that that could just be a coincidence.

It's not a huge deal, I can restart on the fly and since it generally happens when I'm decelerating, the stall does not cause safety issues, but it's annoying.

Will probably go out for another relearn before I try anything else. Will get getting the code for my annual service soon and so this may lead to my first trip down the GTA to get their take on it. From what I've heard I'm not optimistic but I do prefer to make up my own mind about such things. Hopefully that's not an expensive and frustrating mistake.

Does this happen now only with the custom tune you uploaded?