No DFCO

[srgould41]

I am down to just two topics left to complete the tune on my '7747 $42 TBI install. By the way, just had to say how thrilled I am with the fuel economy. I have a Toyota FJ40 with a 305, 4L60, stock 4.10 gears running on 36" tires. With my HEI and Q-Jet I was happy to get 12 MPG. My last highway run got 15.6 MPG for a 30% gain.

My remaining tasks are to get DFCO working (or not if it turns out I hate it) then Highway Lean Cruise.

First up, DFCO. At first I wanted to see if I could make use of DFCO for very slow downhill trail driving. I have given up on that. DFCO in general is not engaging. I have stock parameters and feel the cause is the enter/exit MAP. The remaining values should be easily met. %TPS is also an issue, but only because I have not zereo'd out the TPS yet. TPS is 3 to 4% at idle and the DFCO %TPS is 3%.

My MAP settings are:

Enter 20.63
Exit 31.88

My logs show that I usually run at 33 to 35 KPa on deceleration. I idle at about 45 KPa.

Would the above settings preclude ever entering DFCO?

I envision the following settings to make it work

Enter 35
Exit 39

Can someone advise me on this?

Thanks,

Steve

[RobertISaar]

TPS and MAP are working against you if you want DFCO to happen.

TPS needs to read 0% with a closed throttle(or .39% at most), this effects a lot of the idle control stuff really.

new MAP thresholds look fine.

[EagleMark]

Remember that TPS% is only an estimate off voltage in the $42 definition. If you use the Patch/Hack it is accurate and right out of the ALDL data stream but it takes the place of Knock reading, so knock does not work when using it!

DFCO is no big deal, but you can feel it... a little!