Outer Limits 4x4 Board

Hi
Ok well installing a megasquirt ecu etc , into a 91 rr 3.9 v8 .
I blocked the air valve off to set the idle and can not adjust it above 500rpm .
The manual I read sais to adjust idle with the air valve blocked also so I figure I should be able to get it to idle like this . Before I lift off the intake plenum and clean it out ( suspect it could be dirty and blocked ) can up get a good idle with the air valve blocked off ?

Thanks

Chris

Firstly, pull your rubber intake piping off the throttle body, and get a rag with petrol on it, and clean around and under the throttle butterfly - you may need to jam it open with a screwdriver in the linkage. Then check that the clearance underneath it is 2 thou with a feeler guage - if not, adjust the tiny little throttle stop on top of the throttle body.

Crap inside the actual intake plenum won't give you idle problems, it can only do that if its blocking the path around the butterfly, so taking it off at this stage is more than likely a waste of time, since you can clean the relevant areas with it on the car.

You should be able to get a good idle with the bypass blocked. If cleaning around the throttle butterfly doesn't sort the problem, check that your idle screw isn't binding up for whatever reason....

Hi
Cheers , was only going to lift of the plenum for a good clean . have given it a good clean out , it was not pretty , much oiler than I would have expected . Not good .
Anyway no change to the idle . Did not get the feller gauges home but there is no way there is 2 thou under it , it feels like it closes completely . It can't and tomorrow with a bit more time I will look again .

To adjust the buterfly stop anyone know what tool it is underneith ? Alan key like the idle stop . Will find out tomorrow but guessed someone may know , save a bit of trial and error .

Cheers

Chris

Unless my memory is completely failing and I am too lazy to go downstairs, there is an air bypass screw on top of the throttle blade. You just screw this out a bit.
550 RPM is the correct "kerb idle" for a 14 CUX. (Bosch LE Jetronic.) the stepper then takes it up to target 800 free and 550 in drive,plus the straight increments (100rpm??) for aircon on.
I would have thought that the Megasquirt has a screen for target idle and this should drive the stepper similarly to the 14 CUX. I seem to remember reading that somewhere on the DIY tuning site.
So the kerb idle should be OK as long as it idles.
Regard sPhilip A

Have not had time to look at it again today but it does idle at 550 when warm but only just . Nice and smooth there though .
I only have the cheep v1 of ms so no idle air control valve . May have to upgrade to ms 2 altho in the other thread someone implied v1 can run a steeper motor etc .

Cheers Chris