Redbull-1
That's a great website you located on testing the heater circuit. I found that same website, did the test and posted my results in post #13.

Thanks for the general troubleshooting info. I've been working with that type of equipment and processes for many years due to my job as an electrical engineer.

 

Any suggestions or ideas?

 

I'd say get a OBD2 bluetooth adapter and software to read live data from your PCM.

I read good things about bluedriver, but it is expensive compared to other similar setups. I think their software is better than what I bought years ago ($20 obd2 connector and torquepro on my android phone for $8). chrisfix on youtube has a video review on bluedriver.

I'd say look at the freeze frame, a/f signal, and fuel trims to see how the PCM is interpreting your sensor data to get a direction to diagnose the problem.

 

PAhonda. I agree, that's probably the next step (other than purchasing another car). I just check reviews on the Bluedriver OBDII reader. Their website states it works with "All Honda brands sold in North America after 2003 including Honda & Acura". Unfortunately it doesn't work with my 2001 Accord. About month ago I purchase an inexpensive Bluetooth OBDII reader. It works very well on my 2005 Honda Pilot but won't work with the 2001 Accord. It may have the same issue as the Bluedrive OBDII reader. I will check on the Actron CP96XX reader next unless you have another suggestion.

 

You may want to check in the FAQ section. You can look up the capability by entering your vehicle information.

You said your inexpensive reader doesn't work well. What works and doesn't work with the cheap reader?

 

Good suggestion to check the FAQs. It was under $10, so I just wrote it off. But maybe...

My inexpensive reader doesn't work at all with the 2001 Accord. There is no bluetooth signal to connect to through my Android phone.

 

I've heard that some vehicles require reprogramming of the PCM after changing it. The immobilizer was changed at the same time to allow the car to start and not require reprogramming.
The CEL is on with code P1167. Do I need to get the PCM reprogrammed so the CEL will go off and stay off? I have not read that anywhere but my friend says that's true of other cars.

As an update, I have ordered an Actron CP9680 Autoscanner to monitor real time data. Hopefully this will assist in the diagnostics.

 

The proper denso o2 sensor part number for the ULEV engine is 234-9025 and its a narrow band sensor. The 234-9014 is a wide band sensor also for the same engine F23a4 but might not be the ULEV. I literally just fixed my p1167 code with the 234-9025 denso o2 sensor.

 

Could you please exactly tell me where exactly and how (which panels to take out, etc.) you found the above relays? My 2001 Honda Accord 2.3CL ULEV F23A4 has the same problem. I've done so much readings over the month, but a lot of red-herrings out there. The correct sensor to use is the OEM part number 36531-PAA-306. This A/F sensor has GREEN cover for the wires. Image attached. eBay sells a lot of this, BUT none of them works, as I had bought two already. It must be from OEM part; otherwise, codes P1164/P1167 will stay on.