coxy47 wrote:Ok guys so there have been various methods posted about avoiding a CEL from an underboost code and the truck going into limp mode.
One method was to disconnect the throttle valve to ensure that there was never a vacuum in the manifold. The downsides of this being that it gives an engine light on startup and the shutdown is really rough.
Ive currently fixed this by putting a normally closed relay inline with the throttle valve servo. This is triggered once the accessory circuit is on and it creates an open circuit hence no power to the throttle. As long as you turn the key straight to the off position the car shuts down normally. So far it hasnt given me an engine light on startup not sure why, as i thought it would but im not complaining. This also allows a fully blanked plate to be run without causing a limp mode.
Ill post up how it goes after ive driven it a bit longer and see what happens.
*I cant take credit for this as its based of a post from RHK about 20 pages ago*
Yet another potential fix. Sounds like a winner Chris .