I have some check engine codes

[Ooomph]

Gents,

I pulled a p0138 and p0158 which are "02 sensor high voltage banks 1 sensor 2 & bank 2 sensor 2" (respectively). So both of my sensor two's are reading high voltage. This has only occurred since having my Belanger headers installed. I recently took my car to the dealership and they replaced an o2 sensor under warranty due to it having absolutely no reading. Do you think it's possible they may have left a connection loose? Do the sensors tie together by bank or by sensor number? ie. both sensor one's (bank 1 sensor 1, bank 2 sensor 1) tie together or sensors one and two tie together from one specific bank (bank 1 sensor 1, bank 1 sensor 2).

The check engine light is intermittant but mostly remains lit. Sometimes it will extinguish while driving, sometimes it will light up(if it wasn't already on). Sometimes upon starting/restarting, in either a cold or warm state, it will be extinguished.

Current mods include: K&N filtercharger, Belanger headers, high-flow cats with crossover delete and magnaflow mufflers. The car has also had the factory pcm performance flash performed. Any help would be greatly appreciated.

Thanks,

Thom/New Mexico

 

[SilverSnake]

Thom,

I also just added the Belangers Headers and exhaust system.
So far i have put 1300 miles on and had no problems. Maybe the added insulation to the cat extentions wire loom is missing ? Or call Al let him know what happend. Just some food for thought.

Robert

 

[turbodoc]

That is a tough one. Do you have a DRB III? Possible causes could be 02 Sensor above 1.5 volts, sensor signal shorted to voltage, sensor signal circuit open, sensor signal circuit shorted to 02 heater supply circuit, sensor ground circuit open, sensor heater control circuit open.

Good luck!

 

[Ooomph]

That is a tough one. Do you have a DRB III? Possible causes could be 02 Sensor above 1.5 volts, sensor signal shorted to voltage, sensor signal circuit open, sensor signal circuit shorted to 02 heater supply circuit, sensor ground circuit open, sensor heater control circuit open.

Good luck!

I do not have a DRB III. I used an OBDII reader that I just bought from Roe Racing (which I'll have to say made it to my door 36 hours after I ordered it ). It's just a generic reader good on all or most newer cars.

The thing that strikes me as weird is that apparently whatever is making the o2 sensors read high voltage (or whether they're tied high via an open or short to voltage) is happening to BOTH sensor 2's. Which in turn leads me to the following possibilities:

1.) I am in fact running rich (possibility, but why? wouldn't the pcm adjust?)
2.) The sensor "2" harness is tied high at the point where BOTH banks tie-in
3.) both sensors are faulty (unlikely)
4.) the sensor signal is shorted to high at/near the pcm.
5.) The sensor 2 harness is disconnected which automatically ties the return high (this is just hypothetical, I do not really know if the signal at the pcm reflects ground or high voltage if the harness is disconnected).

I do not have a crossover pipe so I think I can rule out a bad/fouled plug (which would actually create a lean condition from the unburned o2 anyway..) or really anything that only relates to one engine bank. I'm at the point now where I might just start from the pcm and work my way back or vice-versa. Another peculiar thing is that I only got about 200 miles worth of driving after the dealer replaced the original bad o2 sensor, which (good or bad) kind of leads me to believe something worked it's way loose somewhere afterwards.

Thanks for the inputs guys I work better when I bounce stuff off other people, helps me see stuff I never would have looked at. that whole "thinking outside the box" thing.

 

[Dyno Dave]

The "2" sensor on both banks is the downstream O2 sensor which checks catalyst efficiency. Since you have added "high-flow" cats along with the added heat loss to the cats from the Belangers, I would venture a guess that they are not operating to the specs of the OEM cats. Therefore, the light is lit.