bullseyejay wrote:CAN ANYONE TELL ME WHAT MIGHT CAUSE THE ENGINE TICK OVER TO BE UP AND DOWN AND NOT STEADY.. ANY HELP WOULD BE APPRECATED THANKS JAY
which car (model, revision etc)? by how much are the revs changing?
Simle things first: do you have aircon? is it switched to 'Econ' mode? As it cuts in and out the load on the engine changes and revs fluctuate. switch out of econ mode and the revs stabilise.
You have air in the cooling system. The air passing the temp sensor confuses the ECU causing the idle speed to bob up and down. Never happened to me but i've read loads of posts like yours. Will a mk1 owner who has had this problem back me up!?
All you need to do is bleed the system with those flexi pipes (under front bonnet trim) and top up your coolant level.
hth, Jon.
Yep like Jon says, definately check for air in your cooling system. As the throttle body is quite high up where the water passes through it the idle will rise and fall if the cooling system has air in it.