I'm converting my car to a megasquirt and I'm just trying to figure out what runs certain things so that I can figure out what I need to do... Does the stock ECU run the ABS or what? What about the A/C and the P/S..

 

The power steering has it's own control unit and is not connected to the ECU. It will work normally with the Megasquirt. The ASV on the back of the UIM, which increases idle speed when the P/S is used, is controlled by the ECU, and you'll loose that function.

The ABS has it's own control unit and is not connected to the ECU. It will work normally with the Megasquirt.

The A/C is connected to the ECU at two pins. Pin 1E gets a signal when the A/C is running, and the ECU then increases idle speed via the BAC valve. Unless the Megasquirt has the ability to control idle based on A/C input like most aftermarket EMS's, you'll loose this function. Idling with the A/C on could be a problem. Pin 1F is a switched ground for the A/C Main Relay that would give the ECU the ability to turn the A/C off, but it's difficult to tell why exactly. It's possibly if coolant temp gets too high.

 

The ECU cuts the A/C off for about 7 seconds if you stomp the pedal while the A/C is on, to prevent the A/C compressor from robbing torque when you need it. Hence why RX-7s can nicely accelerate when the A/C is on.

 

That's S5 only, not S4.

 

Really? I thought they all did that. My bad. Heh... glad I have an S5 then, I run A/C all the time.

 

You need a full-range TPS for it to work, which the S4 doesn't have.

 

Terrh : I'm going to do this to in my GXL but didn't know where to buy the stuff did you order form there website or where?

sorry for off topic but can't find any info about where to BUY it.


Mage