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Tfi

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Heck52

Heck52

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Glider, I checked out the TFI unit and went through the 3D on how to hook it up. Question is does this unit bypass the ECM or work with it the way I understand that the power commander by fouling the ECM on input data to richen up the mixture. I didn't see where it interfaced with the ECM just the injectors. I'll be back to night, off for now. Thanks
 
The TFI as well as the PC III modifies the pulse width of the injectors to richen the fuel for the engine. It takes the stock signal from the ECM and changes it from there so it is a piggyback unit. The stock map in the ECM stays just that , stock. My feelings are that the RPM limit in the stoc configuration is better for the twin cam 96 engines rather than raising it to the 6200 limit.
 
It actually changes the pulse width just like the PC does TO the injectors, it means longer time opening (cycle time).
 
I'm back. Ok so the TFI or PC change pulse width at the wire going to the injector. I take it it means that the O2 senor is operating at its max range and the ECM won't try to compensate for the added fuel?
 
Heck52 said:
I'm back. Ok so the TFI or PC change pulse width at the wire going to the injector. I take it it means that the O2 senor is operating at its max range and the ECM won't try to compensate for the added fuel?
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The 02 sensor will be at the max adjustable range and probably cannot adjust any more using any tuner. I use the 02 bypass resistors so I can control the fuel myself.
 
Thanks for the input, I'm a diesel marine diesel mechanic by trade and elctronics is just comming in the market. I guess I'll start here. Bit of a different game though. Thanks again.
 
There's two resistors that come with the unit. You unplug from the 02 sensors and plug these into the harness in their place. They keep the 02 sensor code from setting the engine light off.
 
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