my new to me 99 24v when it starts to idle up seems to hammer like holy hell making tons of racket and sounds horrible but as soon as i touch the pedal idle comes back down and it stops till it try`s to idle up again . it has a guad 4k box 7x14 injectors 2.5 turbo and plenty of fuel suppply is this normal for high idle to be like that ? or do i have another issue to work out. it does not matter if the quad is on 0 or any other setting stil lsame thing