what is the reson for this?

[yamaster]

my car has started to act up. here what its doing. the heat sensor light is coming on when i decelerate(take foot of trottle while it in gear) it also comes on when ticking over. but it turns of when i am accelerating.  its still feels perfect when driving.  also the tick over seems to have rissin up to a steady 1100 rpm. it is also nearly dieing if i leave in ticking over to long.(couple of seconds) and it is poping alot more than it used to.

where do i start looking for the problem.    

any ideas what it could be?

car is also decated and all fully maped to suit

[Carl]

my car has started to act up. here what its doing. the heat sensor light is coming on when i decelerate(take foot of trottle while it in gear) it also comes on when ticking over. but it turns of when i am accelerating.  its still feels perfect when driving.  also the tick over seems to have rissin up to a steady 1100 rpm. it is also nearly dieing if i leave in ticking over to long.(couple of seconds) and it is poping alot more than it used to.

where do i start looking for the problem.    

any ideas what it could be?

car is also decated and all fully maped to suit

Call me tomorrow
regards
Carl