So, I want to re-install the BAC valve and am figuring out how to wire the circuit.

The FAQ says:
So, I picked up the resistor and a TIP122 transistor. Is it just a direct replacement? Of course with wiring the TIP in correctly since it is bigger than what its replacing.

The reason I ask is because this page shows the TIP transistor being wired in differently and with a diode:http://www.msextra.com/manuals/MS_Ex...nual.htm#Fidle

And, I've also seen mentioned a diode in a couple of earlier threads that I searched up here.

Do I have to jump R39, remove Q29 and D8 as well?

This is for a MS1 V3 Board.

Thanks in advance!

 

TO220 devices have a different order for their pins than the TO92 devices (the 2n2222a), so it's not exactly a direct replacement. The diagram should be correct.

Ken

 

So I do need to pick up a diode then?

 

One more thing... The R19 resistor, theres nothing about swapping that in the megamanual.

Are these two methods just different ways of doing the same thing? And I should just stick to one? Preferably the one in the FAQ since it only involves 2 parts?

 

The resistor should be 1k. If that's true then you can just use that.

You do need the diode. That's for flyback protection, and should help.

Ken

 

I have done it, and it did work. I used a TIP122 or 120 I think, whatever ken said to use. I removed all the parts he said and bolted it to the heatsink where the VB921 normally goes.

 

I've also set up a few BACs using the modkit from DIYAutoTune. There's no resistor included, and the transistor is a TIP120 I think. Connects directly in place of the stock transistor. Seems to work fine with the stock BAC.

 

I picked up the diode and set it up the way it shows on the link I posted. It seems to work fine on crank, but I think I need to play with the settings still for idle. Its always on 0 dc on closed loop mode. Ran out of time to play with it today, I think its my TPS value keeping it off...