The V8 Owners Forum -

Guys im pulling my hair out, ive got what i suspect as an intermitten air leak.
Im using a twin plenum converted to hot wire - at idle theres no drama as it sits nicely at 900-1000rpm a blip of the throttle and it returns back as it should. Under load the revs will only go back to 1800 rpm.. then if i turn the engine off it goes back to idle at 900-100rpm.

Could this be as simple as a stepper motor issue?

The butterflys are shut tight and it appears the throttles not hanging up.

Before i strip it all down once again any ideas?

mooose wrote:Could this be as simple as a stepper motor issue?

Get it warmed up and then just unplug the stepper motor to see if that is causing the problem?

spend wrote:

mooose wrote:Could this be as simple as a stepper motor issue?

Get it warmed up and then just unplug the stepper motor to see if that is causing the problem?

Nothing happens when i disconnect it is this right?
BIG but if i start the car with the stepper unplugged it over shoots to about 2k plugged in back to 900-1000rpm.
Also if i squueze the pipe from plenum to stepper theres also no gag...

hang on a minute have i just answered my own question

I think the stepper parks open so starting engine with it unplugged should give you a very high idle. Pulling the plug while running shouldnt do anything as the stepper will be frozen where it was before being yanked so I think your stepper is working ok but it is still possible its a bit gunged up so its styicks from time to time. I didn't think the TP had a stepper in it though or has it been added?

No the stepper has been added although a couple of checks today and it seems a bit inconsistant when cycling through the ignition by the key.