Okay i have a low idle problem, checked timing today engine fully warm with a timing light. But if i advance the leading spark approx 15 degrees it idles perfect at 750. What could make this happen???
I read a post by Ddub that said you need a two stroke timing light for a rotary what is the difference?? could this be my problem?

 

Yes you need a 2 stroke light. Advancing timing on a motor at low rpm tends to perk up the idle. This increases your RPM as well if you watch the gauge.

 

So in order to change my idle, I have to advance my timing? In other words, move the screw to the left, instead of the right?

 

So in essence i know a rotory fires twice every 360 degrees unlike a normal 4 cylinder where it fires once every 720. Is this why i need a two stroke timing light??? Or should i just be able to just take a reading of the leading timing and divide it in half to get actual reading??????

 

There was another recent thread that's similar to this one...

Advancing the ignition timing does help idle.
Advancing the ignition also increases emissions.
The stock idle ignition timing spec is made for best idle and emissions compromise.
Advancing the CAS also advances your ignition timing ACROSS THE BOARD.

Don't believe all that crap about requiring a special timing light - this only matters if you have an advance dial / ****, or the timing gun shows an RPM display.
The timing gun just fires the light when it gets a proper trigger through the inductive pick-up - no more; no less.


-Ted

 

mine has a dial on it does that matter???

 

No. You use the fast idle screw on the TB and the BACV.

 

It only matters if you try to use the dial to set advance, then you just divide the advance on the gun by two and that's your actual advance.

Chances are you just have a low set idle/etc and advancing it is just raising it up to normal. I'd try to set it back to stock (unless you want the other benefits of it being advanced), then adjust your idle from there.

 

could a mass air flow cause a low idle??

 

Sonic, what are the other benefits when you advance it?

 

Erase you ever heard the notion...
It's more headaches than it's worth if you don't know what you're doing.
I'd suggest hitting some automotive engine control systems book to understand the relationship of advanced ignition timing on engines.


-Ted