Using O2 Simm while dynotuning?
Using O2 Simm while dynotuning? I am going to be using a wideband O2 sensor in the preCAT position for dynotuning, which means I'll need to plug an O2 simm into the harness. The simms that are available are for the postCAT position. I know the connectors are different. If I replace the connector with the proper one, can I use the postCAT simm in the preCAT position? Will it provide the proper signal to the PCM? Is there another way to do this besides welding in an extra bung? Thanks for the info. <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
Re: Using O2 Simm while dynotuning? I would NOT recommend simming a front O2 sensor.
Rear O2's can be simmed because the computer just wants to see that they're walking around. The fronts actually need to correspond to a real fuel reading
IMHO, spend the extra few bucks and weld in a bung.
Just my $.02, but I hate tweaking on cars that don't have ALL their sensors working properly - including properly functioning O2's. It takes the guesswork out of tuning if you have it all there.
-Andrew
Rear O2's can be simmed because the computer just wants to see that they're walking around. The fronts actually need to correspond to a real fuel reading
IMHO, spend the extra few bucks and weld in a bung.
Just my $.02, but I hate tweaking on cars that don't have ALL their sensors working properly - including properly functioning O2's. It takes the guesswork out of tuning if you have it all there.
-Andrew
On The Tree
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Re: Using O2 Simm while dynotuning? All you need to do is ensure that your LTrims are negative before proceeding to WOT tuning. The primary O2s are not used during PE mode (open loop) so as long as you have the LTrims resolved first you will be fine.
Tim
<small>[ April 24, 2003, 08:54 AM: Message edited by: Tim Sloper ]</small>
Tim
<small>[ April 24, 2003, 08:54 AM: Message edited by: Tim Sloper ]</small>
Re: Using O2 Simm while dynotuning? Thanks guys. I may eventually have an additional bung welded in, but for now I need a way around this. I am heading to the dyno next week to get some baseline numbers. I have heard that some shops use the tailpipe sniffer with good results. any comments?
On The Tree
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From: Orlando, FL
Re: Using O2 Simm while dynotuning? Neither the primary or secondary O2 sensors are used for fuel metering during PE mode. If you adjust the LTrims first you can tune for WOT without the O2s.
Tim
Tim
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From: USA
Re: Using O2 Simm while dynotuning?
Neither the primary or secondary O2 sensors are used for fuel metering during PE mode. If you adjust the LTrims first you can tune for WOT without the O2s.
Tim
Tim
You could be cruising with TPS at 20%, then heavy Accel to lets say 75% TPS,
that would meet condtions for PE but not enough to go from fuel lean ON to OFF
There are also other engine parameters that may not have been met such as engine load)
which would have the same effect as being under 80% of TPS and the following PCM data shows that :
RPM TPS CELL Timing LTFTB1 HO2B1S1 PWB1 MAF DELTQ Load MAFRQ Learn
4448 98.8 22 27.5 0 0.890 14.82 34.8 433.0 92.2 9357.9 OFF
4448 98.8 22 27.5 0 0.890 14.82 34.8 433.0 93.7 9357.9 OFF
4609 98.8 22 26.0 0 0.890 14.82 33.4 433.0 93.7 9357.9 OFF
5612 85.1 22 28.5 0 0.900 14.94 39.3 398.8 100.0 10350.1 OFF
5612 85.1 22 28.5 0 0.900 14.94 39.3 398.8 100.0 10210 OFF
5612 85.1 22 28.5 0 0.900 10.94 39.3 302.5 100.0 10210 OFF
5612 85.1 22 28.5 0 0.900 10.94 39.3 302.5 7.1 10210 OFF
5534 85.1 22 34.0 0 0.900 10.94 2.1 302.5 7.1 10210 OFF
4279 79.2 15 28.0 0 0.890 14.11 30.8 416.0 83.1 9161.6 ON
4279 79.2 15 28.0 0 0.890 14.11 30.8 416.0 83.1 9570.8 ON
4279 79.2 15 28.0 0 0.890 14.63 30.8 427.5 83.1 9570.8 ON
4279 79.2 15 28.0 0 0.890 14.63 30.8 427.5 92.2 9570.8 ON
4448 79.2 15 27.5 0 0.890 14.63 34.8 427.5 92.2 9570.8 ON
3222 76.5 22 26.5 0 0.880 12.88 21.6 364.2 54.9 7828.1 ON
3222 76.5 22 26.5 0 0.880 12.88 21.6 364.2 54.9 8144.5 ON
3222 76.5 22 26.5 0 0.880 13.08 21.6 369.8 54.9 8144.5 ON
3222 76.5 22 26.5 0 0.880 13.08 21.6 369.8 59.2 8144.5 ON
