right need ur help peeps,I start the car up and it goes to 2.5k revs straight away and won't come down.the lad who built my engine last year has had a look and can't find anything.all pipe work is good,changed all the throttle body parts and still the same.now what I need is some advice off a mapper,I got a simtec ecu and can the map drop off and cause this to happen.car was running fine till the oil and filter was changed.thanks

 

No One then

 

If it was running fine until the oil and filter were changed something must have been changed or broken. Retrace everything you did and check sensors and connections.

 

Any one recommend Steve Cotton as a mapper?

 

Idle speed is primarily controlled by air volume, therefore air must be by passing the throttle body somehow. Either the throttle stop is incorrectly set, or the air idle control valve is stuck or being incorrectly controlled, or you have an air leak somewhere. If the throttle is completely closed, you should have very little air going in that way, if any at all, so it must be getting in somewhere else.

 

Could a VTA dump valve stuck open do this?

 

Here we go. Waiting for it!!!!!!!

 

No, that'll just leak boost