[Gmecm] Still Tracker TBI Problems

[David Allen]

  Mosty ECM's require the engine to be run for several minutes under load 
before setting a bad O2 sensor circuit code.
  It wants to make sure the exhaust is hot enough to operate the sensor 
before condemning the sensor.
  A cold sensor and an unplugged sensor look the same to the ECM.
  My car will not flag an unplugged O2 until it has been driven for 4 or 5 
miles.
  The temp, MAP and TPS sensors have a set, finite range of resistance or 
voltage values that are acceptable. Anything outside of this range will log 
a code.  These sensors do not depend on the heat of the exhaust therefore 
any off-scale reading for any amount of time is cause for a code.
  There are other codes for bad signals which have a time factor or are 
dependant on other sensor readings but the basic "circuit fault" codes are 
instant for everything except the O2.
  Hope this helps!!
David

----- Original Message ----- 
From: "Ford, Pat" <Pat.Ford at nrc-cnrc.gc.ca>
To: <gmecm at diy-efi.org>
Sent: Tuesday, February 06, 2007 12:05 PM
Subject: RE: [Gmecm] Still Tracker TBI Problems


> I don't know why it doesn't trip the light either, for me the indicator
> was the heater wires melted. Mine died from water immersion when hot and
> I think the heater came apart and did bad stuff before shorting to
> ground.
>
> Pat
>
> -----Original Message-----
> From: gmecm-bounces at diy-efi.org [mailto:gmecm-bounces at diy-efi.org] On
> Behalf Of Cowen
> Sent: Tuesday, February 06, 2007 12:05 PM
> To: gmecm at diy-efi.org
> Subject: [Gmecm] Still Tracker TBI Problems
>
> Hello folks,in trying to correct high CO and low mileage from my wife's
> 1992 Tracker, I've encountered something I didn't expect.  Yesterday,
> while trying to test the O2 sensor with a multimeter (indeciferable
> readings, will try again tonight), I was running the can with the O2
> disconnected.  It did not trigger the MIL!
>
> Now, the MIL functioned when I disconnected the IAT, so I know the light
> and wiring are good.  How can a sensor as important as the O2 sensor NOT
> trigger the light?
>
> Unfortunately, I was low on time and I didn't try to pull a code last
> night.  Does anyone have an idea why the O2 failure would not trigger
> the MIL?
>
> Insurance runs out Thursday, so I'm getting desperate to find out why
> it's not running right!  To date, I've swapped the ecm, TB, and all
> sensors except CTS (swapping it tonight) with little effect.
>
> Thanks folks,
> Duncan
>
> **********************END TRANSMISSION**********************
>
>
>
> ________________________________________________________________________
> ____________
> Get your own web address.
> Have a HUGE year through Yahoo! Small Business.
> http://smallbusiness.yahoo.com/domains/?p=BESTDEAL
> _______________________________________________
> Gmecm mailing list
> Gmecm at diy-efi.org
> Subscribe: http://lists.diy-efi.org/mailman/listinfo/gmecm
> Main WWW page: http://www.diy-efi.org/gmecm
> _______________________________________________
> Gmecm mailing list
> Gmecm at diy-efi.org
> Subscribe: http://lists.diy-efi.org/mailman/listinfo/gmecm
> Main WWW page: http://www.diy-efi.org/gmecm
>
>