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Discussion Starter · #1 ·
Could someone with an 02' or 03' and a 10mm wrench please do me a favor? Preferably on a relatively stock car. Could you note your fuel level, pop the ECU cover of in the engine bay, disconnect the 5 ECU connectors and turn the key on (don't crank, just on). I'm interested to see what your gas gauge/light does. Based on conversation with Jeff @ TBKO, it appears like the fuel sender is bypassing the engine ECU altogether on the 04'. I'm still waiting on my manuals for the 04', but this doesn't jive with the 02' ECU diagram I have. On mine, with key off, my fuel guage dips below "E" which I assume is the case with the 02-03's. I'm more interested in someone actually trying it rather than heresay. Don't worry, at least on my 04' it doesn't throw a CEL when the ECU is reconnected (with the key off!).

Thanks in advance!

Ryan
 

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i can try it on my car, but as you know, its far from stock

i can tell you the fuel level electricity path

5v output at body ecu, goes through resistance change at sender 1 and then at sender 2 and then goes back to the body ecu, and then it is outputted through MPX1 or MPX2 to the engine ecu, at least on the 02's

-gte



Ryan23 said:
Could someone with an 02' or 03' and a 10mm wrench please do me a favor? Preferably on a relatively stock car. Could you note your fuel level, pop the ECU cover of in the engine bay, disconnect the 5 ECU connectors and turn the key on (don't crank, just on). I'm interested to see what your gas gauge/light does. Based on conversation with Jeff @ TBKO, it appears like the fuel sender is bypassing the engine ECU altogether on the 04'. I'm still waiting on my manuals for the 04', but this doesn't jive with the 02' ECU diagram I have. On mine, with key off, my fuel guage dips below "E" which I assume is the case with the 02-03's. I'm more interested in someone actually trying it rather than heresay. Don't worry, at least on my 04' it doesn't throw a CEL when the ECU is reconnected (with the key off!).

Thanks in advance!

Ryan
 

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Discussion Starter · #3 ·
Hmm...I'm thinking that it's skipping the MPX on the 04's. The only reason I say this is because with the ECU completely out of the loop (like say, sitting in my back seat) I can Key it on and my fuel gauge snaps to the level it was at (what I had before I pulled the ECU). No blinking fuel light or anything. I have an EMS coming this week and then I'll start the harness. Goal first is to run it NA (Sans DBW) before I go yanking the engine. It would make life so much easier. The fewer basic functions (like the fuel gauge) I disrupt the better. On the plus side, everything *appears* to work with the ECU out of the loop. The coolant temp gauge obviously is out but that's not a great concern. To be honest, I was half expecting the power windows and HVAC not to work :lol: . I'm going with the 30-1100 box in case you were wondering. Plans have also changed to incorporate the GTE head/intake. Nightmare, I know... :D

Ryan

IS300GTE said:
i can try it on my car, but as you know, its far from stock

i can tell you the fuel level electricity path

5v output at body ecu, goes through resistance change at sender 1 and then at sender 2 and then goes back to the body ecu, and then it is outputted through MPX1 or MPX2 to the engine ecu, at least on the 02's

-gte



Ryan23 said:
Could someone with an 02' or 03' and a 10mm wrench please do me a favor? Preferably on a relatively stock car. Could you note your fuel level, pop the ECU cover of in the engine bay, disconnect the 5 ECU connectors and turn the key on (don't crank, just on). I'm interested to see what your gas gauge/light does. Based on conversation with Jeff @ TBKO, it appears like the fuel sender is bypassing the engine ECU altogether on the 04'. I'm still waiting on my manuals for the 04', but this doesn't jive with the 02' ECU diagram I have. On mine, with key off, my fuel guage dips below "E" which I assume is the case with the 02-03's. I'm more interested in someone actually trying it rather than heresay. Don't worry, at least on my 04' it doesn't throw a CEL when the ECU is reconnected (with the key off!).

Thanks in advance!

Ryan
 

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i bet it has a memory feature

try doing that, with the ecu out of the loop, and then pull the negative battery cable for a minute and see what happens

*this is speculation, i'd have to see the manual for assuredness)
 

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Discussion Starter · #5 ·
IS300GTE said:
i bet it has a memory feature

try doing that, with the ecu out of the loop, and then pull the negative battery cable for a minute and see what happens

*this is speculation, i'd have to see the manual for assuredness)
Ahhh...good idea, I'll try that tomorrow.

Ryan
 
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