My check engine light blinks for my mercury cougar at idle at every stop light, stop sign, everything as soon as i stop or put it in park it starts blinking whats wrong?

I would first start by cleaning the throttle body with a throttle body cleaner. Take of the air induction tubes and spray a small amount of cleaner into the Bore. Also clean off the mass air flow sensor.

I suspect that if you do not have electric fan/s then the fan clutch or viscous fan hub has failed
indications are over heating at idle , stop lights , slow traffic, high rpms at slow speed but cools down as soon as there is enough road speed to put air through the radiator.

very possible convertor is plugged have local muffler shop check temp difference between convertor an exhaust ppipe also check fuel pressure

Hi,

The overheating and lack of cabin heat both point to a failed engine thermostat which would be stuck closed. At the warm up stage, the coolant stays in the engine block to bring the engine to efficient operating temperature, then it opens and circulates the coolant through the radiator and heat core. If the thermostat is stuck closed, the engine will overheat, and coolant will never reach the heater core, and you will not get cabin heat.

Blinking oil light at idle which goes away during driving could be a low oil level, but may also be a drop in oil pressue. You could have a clogged oil fliter (at best) pickup tube, or a failing oil pump.

mcdevito75 here Sounds like 1 of the fast or air idle sensors are bad, have your shop run a scan.

I'd concentrate on idle air control valve. IAC valve. They control engine idle speed.

Idle sensor is bad. Find a autozone for check engine light they will connect to computer for free, and tell u what codes come up they can give u a printout also.

Hello, here is a thread I found on this site with from what it looks like, the same problem(with an added solution) that you have. http://www.fixya.com/cars/t1576683-1999_cougar_diagnostic_code_p0430_p0420

check all your vacuum lines for cracks and proper connections, (this sounds like a vacuum problem) good place to start..

Check your engine coolant level, if it is low top it off, remember only add coolant to the recovery tank and never to a hot engine, if it is low have the system checked for leaks.