Heated Oxygen Sensor

[Ward Spoonemore]

Several GM app's have the o2 in only one side, but this is not a good idea
since one side tends to run hotter than the other, and thus different o2
results, which side would you choose, Which evee  one you picked woul not be
optimum.

I have the same instalation im my 95 Tahoe, and its a winner. This is the
last of the Lo5 engines for ever !
Ward



-----Original Message-----
From: owner-diy_efi at efi332.eng.ohio-state.edu
[mailto:owner-diy_efi at efi332.eng.ohio-state.edu]On Behalf Of Trevor
Jones
Sent: Thursday, January 21, 1999 9:42 AM
To: diy_efi at efi332.eng.ohio-state.edu
Subject: Heated Oxygen Sensor


I'm not subscribed to this list yet but I'm hoping that some of you EFI
experts can help me out a little.  Since I'm not subscribed yet, any
comments need to be written directly to jones.trevor at towerautomotive.com.

I'm putting a Chevy 350 TBI into my '88 Jeep Wrangler.  The engine that I'm
using came from a '95 suburban with the 4LE60 tranny. It has what GM calls a
heated oxygen sensor instead of a standard oxygen sensor(difference
obviously being it has a positive lead and a ground to "heat" it up as well
as the sensor wire going to the PCM). This oxygen sensor is located on the
exhaust pipe AFTER the two banks of cylinders come together with a Y-pipe.
Would it be a problem if I installed the oxygen sensor on only one bank of
cylinders, or will this adversely affect the computer because it thinks it's
reading from BOTH cylinder banks?   Using only one bank of cylinders, it
would technically have a low reading and think the engine is running too
lean, bumping up the fuel mixture and actually making the engine run too
rich now. Since the engine is getting dual exhaust it isn't an option to put
the sensor on a pipe reading from both cylinder banks. Is this going to make
a difference or will it be so minor that it won't really matter??

Another option is to use a regular oxygen sensor(non-heated) that is made to
screw into the exhaust manifold on one side.  However, do the readings of
these two different kinds of sensors differ, throwing the PCM way off?  Now
the PCM would think it's getting a reading from a heated oxygen sensor off
both cylinder banks, when it's really just getting the reading from a
regular oxygen sensor on one cylinder bank.  Could the PCM or the chip
possibly be different depending on what type of oxygen sensor it had, or
would it function the same with either sensor??

Thanks for any help, it is GREATLY appreciated.

	TJ Jones