imputor

I've had my Melrose smooth-flow exhaust with long tube headers, RT cats, x-pipe, Borla LT1 tip mufflers, and a tune from Bryan at pcmforless.com in my 96 CE LT4 for a couple of weeks now. It ran great at the track, 100mph in the 1/4 and I should touch 13s if I can get a good launch, mind you this is at just over a mile of altitude. It sounds great and is the best thing since the wheel.

But, I've had a check engine light for a bit and it seems to be burning off a lot of fuel when i get off the throttle, the exhaust pops a good bit. I have a check engine light that scans as no signal from sensor one, bank two. I switched it out hoping that it was just a bad sensor. Don't worry I'm not throwing money at it since I'll just return the sensor. Now I need to check the connections and wiring harness. That is the right, passenger side front O2 sensor right? What values should I be looking for on what pins with my multimeter? Engine running or just the ignition on? Any other ideas? No I don't have an FSM, yes I know I need one and that's probably why I'm asking for help.

There is a bit of a rush on this since I need to drive across country soon to drop my car off with family before I deploy. Thank you for all the help I've gotten so far from everyone.

Demonic85

Your not running heated O2 sensor are you? When you get off the gas and the exhaust cools down, the O2 sensor drops out of temp (600* F), goes into open loop and throws a check engine light.

imputor

They are four wire stock replacement bosch 15703 O2 sensors, which as I understand it are heated in the stock application as it is an OBDII car.

imputor

Can anyone help me out here? Looking for any good ideas on why i have the light and how to test if the circuit is working properly.

BAM92

Yes, your O2's are heated. Yes it is the passenger side front sensor. What did you do with the rear one? Deleted it in the tune or use a O2 sim. Did you already change sensor to a new one and if so did anything change?

imputor

Yes i had Bryan delete the rear two sensors, and i replaced the sensor with a new one, reset the code by disconnecting the battery, check engine light is back. Hence I want to do some testing on the wiring harness, but I don't know what values on what pins I'm looking for.

imputor

anyone with any help?

imputor

Please help, I rescanned the code to make sure the reset light wasn't something else. Again it comes up as: P0154

O2 Sensor Circuit No Activity Detected (Bank no. 2 Sensor no. 1)

I checked the connector and wiring harness as best I could without a lift, no breaks and everything looks good and passed the "tug on the wire test."

Any ideas on testing the circuit or where to look would be greatly appreciated, help if in the colo springs area would be paid with a case of your preferred beverage or dinner.

Benny42

Disconnecting the battery doesn't clear the codes on OBD2 cars. Use your
scanner or code reader to clear it and you may have it whipped.
benny

imputor

already cleared it twice with the code reader at auto zone, sorry i didn't specify

imputor

So although it might make me seem stupid, here it goes. I got my car up on the lift this afternoon to check the wiring harness. Went to try and get a better angle on the harness after everything came up negative, low and behold I had the 02 sensor plugged into the deleted rear connector.

Obviously I then attached the 02 sensor to the correct connector. She runs better, no light, very little to no popping from the exhaust, and the butt o meter says better acceleration. I doubt I'll get to the track before deployment so I doubt I'll get you any definitive numbers.

Definitely a duh situation.

RandyJ75

Don't feel bad, we ALL do stuff like that from time to time.