Thanks for the info, Bill and Ray. Both are good bits that I'd not yet found with The Googles.
I had a bit of luck last night. I took the long way home and paid close attention to both O2 sensors on my scanner. I decided to check the readiness monitors a few miles from home and found a pending code (which I can't remember exactly) for rear o2 sensor signal missing! I cleared it, went straight to NAPA, and got a new rear o2 sensor. Shoulda done that when I put the new front sensor anyway rather than just moving the old front to the back.... This morning, the new rear o2 came on faster than the old one did. I thought the ECU actually waited till a certain time to enable it, but perhaps I'm mistaken on that. Anyway, it came on and seems to react much quicker than the old one did. I also saw different freeway behavior. The rear sensor didn't seem to hang high for as long as it did before. I'm hopeful it'll get resolved soon. Gotta go get my 3 month registration extension today... Adam On Mon, Sep 29, 2008 at 8:31 PM, Ray Ayala <[EMAIL PROTECTED]> wrote: > As you've guessed if it's varying between .5 and .8 (staying above .5 > most or all of the time) the cat test will never start. If only the rear > sensor is doing this ... while the front one is crossing the stoich point > frequently ... either the cat is unloading a lot of stored HC's or the rear > sensor is poisoned. A good cat can store enough HCs for this situation to > last several minutes so you might want to defer your observations until > after 10-15 min of steady freeway cruising. One of the cat's main jobs is > to soak up the extra HC's that are produced during warm-up and during > acceleration so maybe you just haven't looked at the numbers long enough > yet. The actual cat test involves intentionally running rich for a short > time to see if the cat actually does soak up the extra HC's, and then see > how long it takes to dump them after the mixture goes lean/stoich again. > Obviously that test can't be started unless the ECU believes that the cat is > fairly empty of HC's. > > ----- Original Message ----- > > *From:* Bill Cardell <[EMAIL PROTECTED]> > *To:* Adam Wolf <[EMAIL PROTECTED]> ; Miata Power > List<[email protected]> > *Sent:* Monday, September 29, 2008 9:02 AM > *Subject:* RE: OBDII readiness monitors... > > You need to look at how it varies. There are some good articles online > about how to test by looking at cross-counts, the number of times the > voltage crosses the stoich point at .45v. Typically easiest to do with a > scope. Some good info here: http://mr2.com/TEXT/O2_Sensor.html > > > Bill Cardell > TurboDog's Dad > www.flyinmiata.com > www.fmwestfield.com > Sales 1-800-359-6957 > Tech 970-464-5600 Before you call, check out > http://www.flyinmiata.com/FAQ/ > > > ------------------------------ > *From:* [EMAIL PROTECTED] [mailto: > [EMAIL PROTECTED] *On Behalf Of *Adam Wolf > *Sent:* Monday, September 29, 2008 9:34 AM > *To:* Miata Power List > *Subject:* Re: OBDII readiness monitors... > > Ok, I got another question. Anyone know what the stock ECU likes the rear > O2 sensor max value to be? Like, is there a high value that makes the ECU > start looking to throw a bad cat code? > > I ask because I've logged some actual interesting data. Got my spiffy > scanner all hooked up - > http://www.amazon.com/Equus-3130-Diagnostic-Capability-Post-1996/dp/B000KID31K/ref=pd_bbs_sr_7?ie=UTF8&s=automotive&qid=1222702093&sr=8-7 > and working. Far more data than the scangauge2. I now know that indeed all > of my sensors are functional. On cruise, my rear o2 sensor reports between > .03 (yeah, point zero three) and .2. Nice, low o2 readings. The reading > tends to live between .03 and .08 most of the time. I see around .5 when I > take off from a light, which seems fine to me. On the freeway at 70-80 mph, > I see a range of .2 to .8, which seems high. Mostly it stays between .5 and > .8.... > > my current theory: these high o2 readings are canceling any o2/cat tests > that the ECU might be getting ready to do. Does this sound at all logical? > > thanks! > > Adam > > On Wed, Sep 24, 2008 at 11:13 AM, Adam Wolf <[EMAIL PROTECTED]> wrote: > >> I've been working on this more (still haven't had the monitors change to >> set). I bought myself a very nice looking scan tool which should arrive >> today, so I'll undoubtedly have more questions/data on this problem. >> >> My new question: is it possible to have the EGR monitor set before the >> O2/cat monitors? I ask this specifically for the 96-97 ECUs. In my (limited) >> experience, the EGR is always the last monitor to set on this ecu. If I >> could get it to set before the o2/cat, all of my problems would be solved. I >> can pass with 2 unset monitors... >> >> thx! >> >> Adam >> >> >> On Thu, Sep 18, 2008 at 12:13 PM, Bill Cardell <[EMAIL PROTECTED]>wrote: >> >>> Matt, email me a fax and I'll send you the factory manual pages on the >>> drive cycle they want. >>> >>> >>> Bill Cardell >>> TurboDog's Dad >>> www.flyinmiata.com >>> www.fmwestfield.com >>> orders 1-800-FLY-MX5S >>> Before you call our tech line (970.464.5600) please check out the FAQ >>> section of our website >>> >>> >>> >>> -----Original Message----- >>> From: [EMAIL PROTECTED] >>> [mailto:[EMAIL PROTECTED] On Behalf Of Matt Bennett >>> Sent: Thursday, September 18, 2008 11:31 AM >>> To: Miata Power List >>> Subject: Re: OBDII readiness monitors... >>> >>> OK, so what are the codes or procedure you need to do to get the >>> readiness monitors? I've got some very basic OBDII tools (like an >>> OBD2-serial port >>> adapter) and I'd like to know how I can read them, and what I should be >>> getting back. I've been looking all over for this information, but I >>> can't find it. >>> >>> Matt >>> >>> On Wed, September 17, 2008 8:32 pm, Ray Ayala wrote: >>> > The rear O2/cat monitors require somewhat specialized driving >>> > conditions for performing their operability tests. Maybe you just >>> > didn't get into the right 'zone' for long enough. They need >>> > fully-warmed-up, steady-state, medium/low torque freeway cruising for >>> about 30 minutes ... >>> > in 'moderate' weather conditions. >>> > ----- Original Message ----- >>> > From: Adam Wolf >>> > To: Miata Power List >>> > Sent: Wednesday, September 17, 2008 10:23 AM >>> > Subject: OBDII readiness monitors... >>> > >>> > >>> > I'm having a devil of a time and I'm hoping the list can help me. >>> > >>> > Car: 97 w/ 99 motor. I normally run the Link, but had to swap the >>> > stock ECU back in for emissions. I swapped ECUs a month ago for my >>> > e-test that has a deadline of this friday. I just took the test and >>> > failed in order to get the 1 year extension. >>> > >>> > So here's new stuff. Some of this has been added over the course of >>> > the last month in an effort to get monitors to set. New front o2 >>> > sensor. I recycled a 30k mile old o2 to replace my original 125k stock >>> >>> > rear o2 sensor that I thought might be "tired". new plug wires (it was >>> >>> > time), new-ish magnaflow cat (about 6 months since putting that in). >>> > Car runs fine. Not as smooth as with the Link, but fine. >>> > >>> > It REFUSES to set the o2, cat, and EGR monitors! I've driven an >>> > honest 500 miles in various conditions. I've performed a handful of >>> > different "drive cycles" I found on Miatanet including one that >>> > claimed to be for a 97 specifically. Still nothin. I can have 2 >>> > monitors not ready in Albuquerque, but not 3. 3 is fail. >>> > >>> > Does anyone have any ideas? I never had this problem before. On a >>> > normal commute to work, this car would run and pass all tests in 2 >>> > days (4 cold-start drives). But 2 years later after running the Link, >>> > there's no joy. I just need to get ONE more test to run. I'm going >>> crazy. >>> > >>> > thanks, >>> > >>> > Adam >>> > >>> > >>> > >>> > ---------------------------------------------------------------------- >>> > -------- >>> > >>> > >>> > _______________________________________________ >>> > Miatapower mailing list >>> > [email protected] >>> > http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower >>> > _______________________________________________ >>> > Miatapower mailing list >>> > [email protected] >>> > http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower >>> > >>> >>> _______________________________________________ >>> Miatapower mailing list >>> [email protected] >>> http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower >>> _______________________________________________ >>> Miatapower mailing list >>> [email protected] >>> http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower >>> >> >> > ------------------------------ > > _______________________________________________ > Miatapower mailing list > [email protected] > http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower > >
_______________________________________________ Miatapower mailing list [email protected] http://list.miatapower.net/cgi-bin/mailman/listinfo/miatapower
