Motech
Just got it firing!
These are likely all the same issue: restricted bypass (throttle) air flow that the ECU stepper commamds are stugging to overcome. That's why the dealership services correct it when they resynch the throttle bodies, providing more bypass airflow, and thereby making stepper work less, followed by an adaptive memory relearn.
Here's a quick check:
When turning on key, allow cluster boot-up to complete. Then engage the kill switch, turn it back off and wait until stepper "whizz" completely stops. Then thumb the start button. If it starts a little better, your issue is restricted bypass air flow. A throttle bore and plate cleaning might cure this. If not, TB synch with stepper bypassed should do the trick.
Another, more intrusive test is to bypass stepper on fully warm engine--either pinch off manifold vacuum hose or plug manifold vacuum bore--and see how it idles. If it won't--if idle struggles down under 750-800 RPM--it's definitely restricted bypass air flow.
Here's a quick check:
When turning on key, allow cluster boot-up to complete. Then engage the kill switch, turn it back off and wait until stepper "whizz" completely stops. Then thumb the start button. If it starts a little better, your issue is restricted bypass air flow. A throttle bore and plate cleaning might cure this. If not, TB synch with stepper bypassed should do the trick.
Another, more intrusive test is to bypass stepper on fully warm engine--either pinch off manifold vacuum hose or plug manifold vacuum bore--and see how it idles. If it won't--if idle struggles down under 750-800 RPM--it's definitely restricted bypass air flow.