MS2 and Automatic Transmission

[kmince]

Dear all,

I purchased a MS2_V3.0 with relayboard for my project on a Ford Focus 1,6L with automatic tranny. My transmission is 4F27E which was developed by Mazda and also used by 2.0 American Focus.

Before starting every thing I like to ask a question about fueling of an automatic car.

Do I live any idling problem with my car when I tune the idle at P or N and then put the gear to Drive? Because load will rise but it has to keep idling smoothly like it always does with EEC5 ECU. I really do not know how EEC5 compensate this load rise and keep idle smooth.

Already thans for your help and answers

[Philip Lochner]

There are several solutions. Here's few I can think of:

1) Program you MS such that timing is advanced for increased load (high MAP) with enough fuel ;
2) install an air bypass valve (called an "idle-up valve" in my part of the world) which is active in all positions except P and N to allow additional air to the engine; I have such a valve on my LR which is adjustable by hand - ex Toyota. This is likely to be the simplest / most successful solution.
3) Implement closed loop idle control (I believe this is possible only with Extra FW) with a PWM idle valve or a stepper motor (IAC)

[kmince]

Philip,

I'm planning parallel instalation with stock ECU and I want to leave idle valve control to stock ECU with GEM modules and tranny. MS will just handle fuel and ignition. I plan to sleave original injector signal with an emulator (this is resistor based emulator which CNG or LPG kits installers use) so EEEC5 will still keep generate PW signal with no control on injectors but it will not understand it is unpluged because it will see the same amount of injector resistance so do not generate error code.

My hope, because it keep generate PW signal under alternate conditions, maybe it can also keep controlling PWM based idle valve as it already do.

If it does not thank you for your suggestions I will keep in mind and apply them. Any additional info or suggestion will help me a lot.

Murat

[Philip Lochner]

Hi Murat

Many MS installers keep the original ECU for various reason including gearbox control and timing control.

I am quite certain you could retain the original ECU to also control the idle valve in which case the engine should be pretty much the same as it is now. Just make SURE that the engine gets enough fuel in the area of idle as lean spots can rapidly cause idle instability.