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Gen 3.5 Drop In Cruising Gas Mileage

Is the Doctor still in the house? Did you ever get this issue resolved, where your gas mileage dropped about 10mpg after installing the Gen 3.5 TFI unit.

I ask, as I recently installed a TFI unit as well, and my mileage dropped from 41-43mpg on average, to 33-34 mpg. This checked across 3 tanks of gas.

I'm easy on it so it's not a heavy on the throttle issue. Turned pot #2 (yellow) to off on this last tank of gas. The other 3 are set to TFI's recommended setting. Still getting low 30's mpg.

I've not opened a case for it yet, as it's one that's on the list. But curious if you ever got your issue resolved - thanks

EDIT - only other mod I have, aside from the TFI, is SE Touring Street Performance mufflers. Still running stock a/c
 
The TFI is a great unit and easy to set up too. The settings that are furnished with the unit are a tad on the rich side which equates to lower MPG.

I would recommend being you only have the mufflers and not the intake to unhook the ground wire and then recheck your MPG over a few tanks to be sure it's not a different style of driving causing the lower MPG.
 
I ask, as I recently installed a TFI unit as well, and my mileage dropped from 41-43mpg on average, to 33-34 mpg. This checked across 3 tanks of gas.

Never used one myself but would say Pot #3 ("main fuel adjustment") needs to be turned back a bit. Especially with using the stock A/C. Sounds like your screaming rich at cruise range.
 
Never used one myself but would say Pot #3 ("main fuel adjustment") needs to be turned back a bit. Especially with using the stock A/C. Sounds like your screaming rich at cruise range.
This is exactly what Dallas (Dobeck) told me when I installed the gen3 on my otherwise stock set-up. So I was expecting a drop of a mile or 2 per gallon but in reality there was not much change ...at least not enough to get excited about.
 
Thanks fellas - I put the ground wire on that center post of ground wires just to the left of the front tip of the seat. So should be easy enuf to do that.

I've not messed with pot #3 Hoop, but think I'll disconnect the ground wire 1st, run a check - and if the condition corrects itself, will reconnect ground and back off #3 1 position setting. I don't have my notes in front of me of what the current setting is - but think that's how I'll approach this.

Appreciate guys -

Should note as well that I don't have a Gen3 - it's the 1254 unit (I think thats the mod# - whatever the unit is that's compatible with the 08 EGC)
 
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