---===The Official MAFT-Pro Thread===---

[TurboBob]

Originally Posted by RobBeck

DC start is way too low. i had same troubles because i read the directions rather than using common sense. bump it up to about 30+ or so and you will start to see good #s.

Rob

The instructions are VERY conservative, because you never can tell if the customer is going to set it right.......

I suppose the instructions should contain some details about what to do after you first set it and try it.

Rob is right, leave the gain low (like you have it) and turn the start DC up until your boost is about where you want it. Then turn the gain up to 10 or so and it will control your boost at the set PSI.

Bob

[lord sargent]

i set the dc start to 30 and the gain to 10 and it did the same thing.... boosts to about 12 then dives back to 3 where it holds.

i set the dc to 100 to see if it would keep the wastegates closed, and it did.

Originally Posted by TurboBob

The instructions are VERY conservative, because you never can tell if the customer is going to set it right.......

I suppose the instructions should contain some details about what to do after you first set it and try it.

Rob is right, leave the gain low (like you have it) and turn the start DC up until your boost is about where you want it. Then turn the gain up to 10 or so and it will control your boost at the set PSI.

Bob

[TurboBob]

Originally Posted by lord sargent

i set the dc start to 30 and the gain to 10 and it did the same thing.... boosts to about 12 then dives back to 3 where it holds.

i set the dc to 100 to see if it would keep the wastegates closed, and it did.

Sounds like the solenoid is installed reversed

Bob

[Rustang Cobra]

Originally Posted by lord sargent

the problem was (or at least part of) the tps connection at the TPS


and the boost problem... it will boost til about 9, and then drop to 3....

im about to just give up...

the issues you're having are user error issues, you would have the same problems if you installed an afc or emanage incorrectly....you can't be frustrated with anything other than yourself

you really have to solder the connections, i honestly think bob should stop including the t-tap connections because it just promotes problems that can be easily avoided


as far as the solenoid goes....

my DC start % is 75 and i run around 16psi

50% will get you around 12psi

30% will get you 6-8psi

14% will get you 6psi or slightly less


i also think you installed the solenoid backwards

[lord sargent]

yes, im fully aware that the problems are my fault, the part about giving up was a joke...

when i installed this i knew it was going to be a pain in the ass to get it working right, but i planned to use it as a learning experience, and so far, it has been. the best way to learn is to make mistakes, ive made my mistakes, and i have learned from them.

this weekend i will be redoing all the connections (this time the right way) and fixing the TPS.

and thanks for the advice with the DC

also, i installed the BC exactly how the instructions said to. so i installed it backwards if the instructions are backwards.

Originally Posted by Rustang Cobra

the issues you're having are user error issues, you would have the same problems if you installed an afc or emanage incorrectly....you can't be frustrated with anything other than yourself

you really have to solder the connections, i honestly think bob should stop including the t-tap connections because it just promotes problems that can be easily avoided


as far as the solenoid goes....

my DC start % is 75 and i run around 16psi

50% will get you around 12psi

30% will get you 6-8psi

14% will get you 6psi or slightly less


i also think you installed the solenoid backwards

[Storm Strike]

Another question about tuning with the stock O2's unplugged. Will the stock ECU react differently to different steady voltages on the O2 lines? Say if I feed 0.2 V from a regulated source into each O2, what will the ECU do with fuel trims, vs feeding it 0.7 V? Could this be used to keep the fuel trims around 100%, rather than having them peg at max rich? Also, might it keep the ECU from throwing CELs?

[TurboBob]

Originally Posted by Storm Strike

Another question about tuning with the stock O2's unplugged. Will the stock ECU react differently to different steady voltages on the O2 lines? Say if I feed 0.2 V from a regulated source into each O2, what will the ECU do with fuel trims, vs feeding it 0.7 V? Could this be used to keep the fuel trims around 100%, rather than having them peg at max rich? Also, might it keep the ECU from throwing CELs?

With the O2's disconnected the ECU sees 0.0 volts, The ECU doesn't move the trims until after it sees the O2 voltage start to move.

If you fed a .2 volts, the ECU would run the trims to max, to try to raise the O2 voltage.

If you fed a constant .7 volts, the ECU would run the trims to minimum.

Once pegged out, the ECU gives up, and switches to open loop, but the transition is not smooth....

The only way to hold the trims at 100% would be to feed an O2 voltage into the ECU based on the trim values. Not sure how to do that...... (the Scanmaster could be made to do it, with some work....)


But, the trims DONT peg rich when you unhook the O2's
(as far as ALL the guys here who have tried it have found.....)
(except for Shiver, I guess......)

As far as preventing the CEL, I'm not sure how to do that. If you fed a constant .45 volts, theoretically, the ECU will think that the trims are perfect, and not move them...... unless there is some logic that requires the O2 to toggle to prevent the CEL.....

Bob

(The preceeding is based on my findings, and reported results of others)

[Quick Vr4]

can't you just run a wideband on the rear bank and narrow band on the front bank. Then tap the fron 02 sensor wires into the connector for the rear o2 sensor?

[TurboBob]

It might work.

As well, I have not tried unplugging just one O2.

However, you are asking for trouble running the wideband sensor that close to the turbo.

B

[Barefoot]

Originally Posted by Quick Vr4

can't you just run a wideband on the rear bank and narrow band on the front bank. Then tap the fron 02 sensor wires into the connector for the rear o2 sensor?

I actually ran like that for a few months.. never threw a CEL, but i did have to replace the wideband sensor