megasquirt idle

[fastcomet]

Putting a new intake on today with big throttle body. To clean up hoses etc. Can megasquirt take care of idle by cracking the throttle blade instead of running Idle Control Motor. Which I replaced long ago with a check valve. Car is a 93 volvo 240 with plug and play MS. Thanks

[JohnMc]

Megasquirt can't control the throttle blade, if that's what you're asking.

You could set the idle by adjusting the throttle slightly open, but that will be fixed, not controlled.

[Marvelous3]

Not unless your throttle body is electric.

[fastcomet]

Sorry if my question wasn’t real clear. I guess what I’m asking is can I plug the idle control hose fitting in the intake and remove all the extra idle c. Motor. And just crack the throttle blades manually to control the idle speed? I would think I could but I’m not positive.. thanks guys

[JohnMc]

Originally Posted by JohnMc

Megasquirt can't control the throttle blade, if that's what you're asking.

You could set the idle by adjusting the throttle slightly open, but that will be fixed, not controlled.

This may or may not be annoying. Do you have working A/C? Other than that, you'd probably need to keep your foot on it when it's cold.

[Harlard]

You can have it manage idle speed with an ignition timing adjustment curve once you set your desired speed by cracking the throttle blade. You will have to feather the throttle with your foot on cold starts.

Also, reread the Tunerstudio reference guide cover to cover. This is covered in detail in the product documentation.

[cwdodson88]

Originally Posted by Harlard

You can have it manage idle speed with an ignition timing adjustment curve once you set your desired speed by cracking the throttle blade. You will have to feather the throttle with your foot on cold starts.

Also, reread the Tunerstudio reference guide cover to cover. This is covered in detail in the product documentation.

What ^ said.

I'm working up a design for a choke bellcrank/cam thing. I had a couple ideas, one was to tickle the throttle pedal, the other was the throttle body. you just need that tiny bit on those cold mornings.

[90volvo]

Timing deal would make it simple.

[fastcomet]

I dont mind keeping my foot on throttle as its warming up. Im switching intakes out tonight and just thought Id clean up engine comp. a bit and get rid of things that I dont need. Intake has volvo 960 tb, i worked on the intake injector bossws some, to help with air flow. Dont know if its gonna help any but sure cant hurt anyting. Also replacing a V cam with RSI stage 2. I hope I can get into the 13s. Only time will tell. Thanks for the help.

[John242Ti]

That would probably get annoying, especially with a hotter cam that is going to have a more lopey idle than a stockish cam. In fact, I know it's annoying, since my 242 is currently requiring that I hold the throttle open, due to a non-functional constant idle system. Also, Volvo does have a warning saying not to "race" a turbo engine when cold, even though the constant idle air valve does that initial blast to 2000 rpm before it settles down to idle.

Personally, what I'd do, if you don't want a constant idle air valve, would be to run an auxiliary air valve from a non-constant idle B21F. Has a bimetal spring in it that causes the disc inside of it to open and close, depending on temperature. Requires 12 volts power and ground. Set idle to whatever makes the car run smooth enough when warm, then, when the engine's cold, crack open the throttle a little before starting, then release as soon as it fires. Engine will run around 1500ish rpm until the valve gets warm enough to close itself.

[142 guy]

The idle / ignition advance control in MSExtra is meant to help stabilize idle speed for small idle speed variations. Not really an idle speed control mechanism. The idle advance is normally only activated when the TPS shows closed, the RPM is less than around 1000 RPM and the engine is up to operating temperature. You can fiddle those settings; but, you are trying to get the idle advance system to do something it was never intended to do. The advance curve that you program in would normally raise advance when idle speed drops below your target idle speed and reduce advance when the idle speed rises above your target idle speed.

You could set the idle advance to control around your normal target idle speed (800 - 900 RPM?). You would normally have it deactivated during warm up or doing a hot start so it will have no benefit during those operating conditions. The idle advance system is not designed to make big changes in idle speed control, that is what the idle air valve is for. If you try to bodge it by opening up the parameters and allowing huge amounts of advance or retard from base setting you are likely going to create transition issues going from idle to driving or find that the system is fighting you during the warm up period.