P1166 and funniness from ECU

[firedc5s]

so here is the deal.

I got Kpro and everything has been jolly and dandy up to a couple of weeks ago.

my a/f was reading fine until about 1 month ago when i got a CEL that said that there was no activity from primary o2 sensor and the lamda was not reading. I was like ok... turned off the car and turned it on... and the lambda read again and the cel did not show up again... fast forward to the day before yesterday...... I was driving and all of a sudden got a CEL and my lean cutoff wouldnt let me go full throttle. Im like ok. I turn off the car and then turn it back on and i still have a cel but i dont have lean protection cutting me off... so the A/F is reading. I get home and i check the code and it is P1166 primary heated 02 sensor heater circuit malfunction. I was like ok.. and i reset the ecu. Yesterday morning i get in my car and the stupid CEL comes on again and my lambda (A/F ratio) is not showing and my O2 sensor voltage is zero.

So i checked for loose pins and there are none so i figure its either the ecu or the primary o2 sensor. so i pulled my ecu out of my car and plugged it into my friends car. Then the weirdness started to happen.
The connection with his onboard computer keeps dropping and coming on and off. When it is online and ignition on, when i press datalog the connection cuts.. and when i upload a calibration, it says upload failed.
This did NOT happen when he plugged his ecu into his computer though.


So then we used my computer in his car(with my ECU plugged in), it was uploading the calibration really slowly and when we started the car the A/F was reading. The O2 sensor was also getting voltage. About two minutes into it we got a code for O2 sensor inactivity. We turned off the car and turned it on and we got an A/F readout and we kept the car on for 8 minutes and no cel and a consistent A/F readout.

I tried with my computer hooked up to my ecu in my car with my computer and it works perfectly except for the AF issue.

HONDATA WHATS UP WITH MY ECU? I am replacing my primary O2 sensor because that seems to be the problem.. but why did my A/F ratio error on my friends car? Could there be something wrong with my ecu? If so, would this be repaired under warranty. I have heard of problems with A/F when people run o2 simulators, but i dont have one nor have i altered the stock wiring of the primary or secondary sensors in any way. What gives?

[Hondata]

Check the o2 heater wiring as per the manual.

Do you still have a cat?

[firedc5s]

Check the o2 heater wiring as per the manual.

Do you still have a cat?

i dont, im running a dc race header... the o2 heater wiring?? but i never messed with the harness in anyway.. and there is voltage going through the wiring... i tested it with a voltmeter... there is voltage coming from the ecu to the sensor....

[Hondata]

1. Uninstall KManager. 2. Download KManager from here 3. Install KManager using the file you downloaded. 4. Select your calibration (do not download it from the ECU). 5. Upload.

If you have problems uploading, then go here and fill out the form.

Have you disabled the OBDII functions ? P1166 often means that the ECU is still looking at the secondary o2 to check the output from the primary o2 sensor.

[firedc5s]

hey,

i replaced my o2 sensor and i seems like the a/f is reading.. One last question though please. When i turn on the car to stage2 ignition, my primary o2 sensor is 0.00 but my s02 is reading. the primary o2 sensor voltage is 0.0 until a couple of seconds (5-7) after i turn on my engine and then it starts reading fine...... is this normal?

[Hondata]

Yes, the primary o2 takes about 10-20 seconds to start reading.

[firedc5s]

Yes, the primary o2 takes about 10-20 seconds to start reading.

10-20 seconds AFTER u start the motor right? because my primary o2 reads 0.0v in stage 2 ignition