Bank 1 and 2 sensor 1 no activity

**Tx98Formula** · 03-04-2010, 06:21 PM

98 Formula LS1 A4, has LT headers, manual cut out, k&n, slp lid, small cam, and a tune.

I keep getting p0134 and p0154 ses codes.. it has 2 brand new bosch O2 sensors, the driver side has a brand new harness extension on it, from what i have seen i don't see any melted wires, no cut wires, no broken connections at all.. i can't figure it out.. the only thing i haven't done yet is hook up a tester and check for proper voltage, mainly because i'm not sure how to test the O2 sensors. So... how do you go about testing the O2's to make sure they are actually working?

if anyone has had an issue like this please help me out.

**pajeff02** · 03-04-2010, 06:25 PM

Easy test is to swap the sensors side to side and see if the problem follows. Other than that, you can probably use a DVOM to check them. I know I have tested the heater circuit via a continuity tester -- just never had to check actual output. If I recall, output will be in millivolts and it fluctuates widely up and down as the car is running.

**0rion** · 03-04-2010, 07:02 PM

the easiest way I know is to log it with hptuners or something like that so you can watch the voltages switch. Who tuned the car?

**Tx98Formula** · 03-05-2010, 03:08 AM

Both o2's are brand new, and they both seem to fail at the exact same time.

For the tuning I sent the PCM to Solomon at lt1performancetuning.com.

I just don't know how or why they fail at the same time. The only thing I know of that they have in common is the PCM?? Or is there anything else they have in common?

**Tx98Formula** · 03-05-2010, 06:52 AM

i drove the car into work this morning. I cleared the codes before i left the house and didn't get them back till about 10minutes into the drive. This time all i got was a P0134 (B1S1 no activity) P0135 (B1S1 heat circuit malfunction) and P0155 (B2S1 heat circuit malfunction)

i read somewhere else, that there is a fuse near the battery to check, also to check all the grounds and for the O2's.. I'll try and get out there to do that today after work sometime.. if anyone else has any ideas please let me know

**Cutlass** · 03-05-2010, 10:33 AM

if the heater circuits aren't working that could cause the activity codes

**Tx98Formula** · 03-05-2010, 10:44 AM

another question... i know on bikes you can bypass the O2's using a power comander and what not. can you do that on these cars? just bypass the front O2's using a tuner or something?

**pajeff02** · 03-05-2010, 11:11 AM

Originally Posted by Tx98Formula

another question... i know on bikes you can bypass the O2's using a power comander and what not. can you do that on these cars? just bypass the front O2's using a tuner or something?

The front O2's control closed loop fueling -- you need to maintain these. The rear O2's simply tell the PCM if the cats are working. These can be tuned out.

**pajeff02** · 03-05-2010, 11:13 AM

Originally Posted by Cutlass

if the heater circuits aren't working that could cause the activity codes

Agree. I think a simple continuity test of the two (2) white wires will show a blown heater circuit. But check me on the wire color please.

**Tx98Formula** · 03-05-2010, 01:08 PM

the other thing is its not just the heater circuit, i am also still getting p0134, 154 and 131 and 151 codes (no activity, and low activity) i think there might be some ground wires maybe that aren't connected maybe... i'll shoot some continuity

**0rion** · 03-05-2010, 03:45 PM

what was the part number of the sensor you used and how often does it throw those codes? Have you cleared them and how long does it take for them to come back? When exactly did it start throwing them and has it thrown them across 2 different sets of sensors ( stock ones and the new ones)?

you can tune the car in open loop and do away with the front O2's but if at all possible I would get those O2's working if you can.

**Tx98Formula** · 03-05-2010, 04:13 PM

not sure of the exact part number on them, they are the direct OEM replacement Bosch O2's, got them at autozone.

I clear the codes everytime i park the car. I get the codes about 5-10 mintues into each drive, seems about when the car hits its normal running temp (around 180ish). It has thrown O2 codes since i have had the car (bought it late January). It was kicking out Low and No activity codes through both sets of O2's that have been in it.

**Tx98Formula** · 03-05-2010, 04:14 PM

part number on the O2's i have (13444)

**0rion** · 03-05-2010, 04:25 PM

kind of a weird situation IMO....the odds of both new O2's being bad are next to nothing so you can almost rule the O2's out. Was there one change or some mod or something where this started happening?

**Cutlass** · 03-05-2010, 04:43 PM

Originally Posted by Tx98Formula

the other thing is its not just the heater circuit, i am also still getting p0134, 154 and 131 and 151 codes (no activity, and low activity) i think there might be some ground wires maybe that aren't connected maybe... i'll shoot some continuity

Start by diagnosing the O2 heater circuit. Its somewhat likely all your O2 codes are related to one problem

**Tx98Formula** · 03-05-2010, 04:46 PM

i changed nothing before this started.. when i bought the car it had O2 issues, along with a few other wiring issues.. i fixed everything else (had #3 misfire, then random misfire) now just stuck with the O2 issue..

**Tx98Formula** · 03-06-2010, 03:33 PM

ok i went and bought a tester to check all the wires and what not.. I unhooked the harness extensions from the engine bay harness. I tested the ground to the O2 sensor and that was good. Then i tested all the wires on the engine bay harness (pink, purple, tan, and black) The pink one is the only one that moved away from 1 on my tester, it jumped up between 60 and 58.xx.. The ground (black wire) never changed it stayed at a constant 1.0, which is what the tester is at not touching anything.. This was the driver side O2 harness (didn't have time to check passenger side)

So here is my next question.. can i cut the ground that is on the engine bay harness connector and just run my own ground for that? that just seems like it would be an easier solution then trying to dig through that entire harness all the way back to the PCM..

**Tx98Formula** · 03-06-2010, 05:59 PM

if anyone can help me out i need to know if i can do that with the ground wire as soon as possible.. if its ok to just tap into that ground wire right after the connector i plan on doing it tomorrow so i can get this car running right...

thanks

**0rion** · 03-06-2010, 06:07 PM

I honestly have no idea but I would think it won't work. Not sure though, hell I'm not even sure where they ground stock. I would've thought at the pcm but just glancing over the pinouts I don't see the grounds for it. 98 pinouts
What kind of extensions do you have? Home made or store bought? It feels like I'm overlooking something here but for the life of me I can't figure out what it is.