Converting 94-95 MS1 in // to Standalone - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to   Members

MEGAsquirt A place to collectively sort out this megasquirt gizmo

LinkBack Thread Tools
Old 08-29-2010, 07:49 PM   #1
Senior Member
Thread Starter
iTrader: (1)
Join Date: Oct 2009
Posts: 1,436
Total Cats: 58
Default Converting 94-95 MS1 in // to Standalone

I'd like some confirmation on my EMS. Next year, I plan to start doing track days and want full control of the fans and idle to do so. I understand the unit I have currently is a 94-95 MS1 PCB3.0 w/ EBC in parallel, so the factory computer still controls idle, fans, and a/c. I'd like to verify what I'll need to convert to standalone:

Remove the tie-ins from the MS1 from the factory ECU

Then add:
Relay Control Mod-Kit
PWM IAC Valve Control (TIP120) Mod-Kit
Consider adding A/C control via Joe Perez instructions
64 pin connector (174518-7)

Last edited by Enginerd; 08-29-2010 at 08:06 PM.
Enginerd is offline   Reply With Quote
Old 09-06-2010, 12:04 AM   #2
Senior Member
Thread Starter
iTrader: (1)
Join Date: Oct 2009
Posts: 1,436
Total Cats: 58

Well, I started out today by installing the fan control. Oddly, the EBC that was installed previously does not even appear to be wired to the correct pin.

On my board:
IAC1A & IAC1B are used for the spark outputs.
IAC2B is used for EBC.
IAC2A is what I used for the fan output.

Oddly, the harness output is connected to pin 29 for EBC...but the best I can appears that this should have been connected to pin 31 to match IAC2B on the PCB...?

I soldered the fan output into the respective pins on the backside of the factory PCB. The car started up and ran fine, however the coolant and ait temperatures were 33F from a baseline cold start. Ambient temperature was 66F...did I screw something up here, or is this duplication between the factory PCB resistors and the MS? Prior to adding the fan mod, coolant temperatures were low like that, however the ait temperatures were correct when it was hardwired directly to the MS. Also, the fans were continuously on from the moment I turned the key.

I'll post pictures if needed (let me know if that may help). I could use a few hints:

Are the pin outputs I've used correct:
IAC2A = pin 29 (fans) and IAC2B = pin 31 (EBC) ?
IAC1A/IAC1B = pin 36/27 must be correct as the car runs perfect with that orientation.
Why would the fans turn on immediately? This should be coolant temp controlled, correct?
What causes the temperature readings to be so far off?

Last edited by Enginerd; 09-06-2010 at 12:14 AM.
Enginerd is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
Looking for some EMS4 help E=MC^2 DIY Turbo Discussion 29 10-20-2015 01:03 AM
Odd Steering issue interestedofold Suspension, Brakes, Drivetrain 5 09-29-2015 02:42 PM
Tan convertible top and frame 95-97 DonPlatt WTB 0 09-01-2015 09:07 PM

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -4. The time now is 03:33 AM.