Here is what I am trying but it is giving me trouble.
rem Engine sounds
load sound "Sounds\engineidle.wav",1: set sound volume 1,100
load sound "Sounds\EngineMidRPM.wav",2: set sound volume 2,0
load sound "Sounds\reverse.wav",3: set sound volume 3,0
rem set gas and brake keys and engine sounds
key = 0 : force#=0.0
if upkey ( ) = 1 then force#=60 : key = 1 : phy set vehicle wheel multiplier 2,50
if upkey ( ) = 1 then force#=60 : set sound volume 1,0
set sound volume 2,100
if downkey ( ) = 1 then force#=-185.0 : key = 1 : phy set vehicle wheel multiplier 2,-50
if downkey ( ) = 1 then force#=-185.0 : set sound volume 1,0
set sound volume 2,0
set sound volume 3,100
if key = 0 then force#=0.0
phy set vehicle motor force 2,force#
if force#>0
forcenoise#=forcenoise#+(force#/10.0)
if forcenoise#>4000.0 then forcenoise#=4000.0
else
if force#<0
forcenoise#=forcenoise#-20.0
if forcenoise#<-500.0 then forcenoise#=-500.0
else
forcenoise#=forcenoise#-50.0
if forcenoise#<0.0 then forcenoise#=0.0
endif
endif
