[Ody Fan Club]

I know I'm digging up a thread from a year ago but I wanted to continue the discussion a bit.

I had an intermittent CEL, pulled the codes at Autozone and got a P0401 and P0420. I cleaned out all the gunk in the EGR port with a 17/64ths drill bit, did some other cleaning in the intake/EGR valve and put it back together with a new throttle body & EGR valve gasket. I pulled the battery cable for a few minutes to reset the codes, drove it around a while and went back to Autozone. P0401 is gone but P0420 is back...the weird thing is the CEL never came on.

So...what does the P0420 code with no CEL light indicate? Is there something in between "normal" (no light) and "bad" (light) that the computer stores that indicates "the CAT is going bad but not gone yet"? I have never smelled the rotten egg smell so I would guess it is not the CAT (or is that not necessarily always a positive indicator of a bad CAT?). Or could it be the secondary O2 sensor?

 

[Ody Fan Club]

To help determine if it ia a problem you need to check the readiness code. If it is complete and ready it was probably a temp failure.

I've never heard of the readiness code...can you enlighten me? I'm assuming that cannot be seen without some ODBII software or through the dealer's diagnostic equipment? I've been looking for something that can display the various sensors, their readings, be capable of possibly adjusting some things, all through a laptop.

 

[Ody Fan Club]

William...I browsed the obd-2.com site. Alex Peper's credentials and history with OBD is impressive...he's the man! And the software interface looks pretty slick. So for $122, you get the connectors and software that runs on your laptop and is able to access the OBDII info. I have a Honda and a Nissan so all I need is the ISO network and can use it on both cars. Am I missing anything?

How long have you been using the software? Is looks like it is able to store sensor/performance data on your laptop? What shortcomings have you found with the software, if any?

If I got the software, I'd be able to check, among other things, my O2 sensor performance to make sure they were working properly...

 

[Ody Fan Club]

Quick update - after driving the van around for a week, I took it to Autozone Friday to check the codes again. My wife said she had not noticed the CEL on the entire week. Autozone guy plugged in the code reader and voila, no codes found!

I was happy driving around for the rest of the day until the next morning, when I noticed the CEL light on again!!! I was going to go back to Autozone but had a bunch of other errands to run so didn't get a chance to. During my errands, I noticed that the van had been turning over slightly slower than normal so I checked when I had replaced the battery last and sure enough, Jan 9, 2004, almost 3 yrs to the day. My experience is the Honda OEM batteries (and replacement batteries) seem to have a 3 yr timer on them...I have had at least 3 go bad within a few months of their 3 yr anniversary (original battery in the van lasted 3 yrs 2 months).

Since it was a Honda replacement battery, I went back to the dealer to have them load test it and at least recoup 40% of the cost covered on the 5 yr prorated warranty (it was 11 days past the 3 yr full replacement anniversary). The battery failed the load test with only 300 CCA available. My service advisor Neil (same guy that handled my two warranty tranny replacements and politely told me that they couldn't do anything about the EGR TSB due to 116k on the van) said "Well, let me find out what I need to do." Less than 10 minutes later, they had a replacement battery for me and I was on my way with no discussion about the prorate! Incidentally, Honda replacement batteries now have a 100 month warranty for about the same price ($65) as many other 60 month batteries out there...and no modifications required to battery cables/hold down/etc.

This is evidence that it does pay to get to know some of the service and parts guys at the dealer...