pcmhacking.net

what about using the tach output from the DFI? might just need to be amplified to 12V? iirc the tach is 5V square wave?


You can work out what the frquency for 1500 rpm is and then get a generator to input that to the cruise module, then enable cruise, then once the module is enabled switch the signal over from the frequency generator to the tach and it should see the drop and pick the rpm up to 1500 and hold.

im not sure but i think cruise would have toooo much response lag ....
need's to have fast response both way's ...

Arduino project ?

yeah ... im good with PIC's ... also have a duinomite here .(basic) .....
a MELSEC FX2N would be good ... it has PID instruction ... but i don't have one ...

cruise control is more than fast enough if they respond to bumps in the road and you think bout how short of the time the rear wheel/s spend in the air.

Also watch how fast the engine goes to red line if you put it in neutral on a level road after only a drop of 1 or 2 km in speed. I think hey would be more than enough for the task and would simplify the project a lot. you could just make a simple controller to handle signalling and enabling. And you also have the benefit of emergency cut out input which you could use the PCM to cut the cruise out if say engine temps or rpm exceeded a certain amount.

Why not stepper in place of the IAC?

Simon

IAC is a stepper though.

IAC stepper would be ideal if PCM could hold 1500rpm closed loop...

how would i set 1500 on cruise control..?

I already explain in a previous post.