Low or bad battery. Bad connections on battery posts. No connection through the ignition switch to the starter relay. Relay defective. Cables loose. Starter bad. A simple voltmeter is very helpful on these repair problems.
I do not have a answer for it, do you an answer for this problem?
Engine Seized?
It's a mercury cougar. I'm afraid this car has problem after problem and needs to be not driven. That aside, 1. starter is bad 2. battery is bad 3. wire problems (very possible with this genius wiring system in these cars) 4. engine seized 5. fly wheel seized. Could also be a short in the ignition column. Wiring problems are wicked bad with these cars for sure.
The engine might not be getting any fuel. The engine may also have weak or no fire at the spark plugs. Check these two places to find the problem.
Since the starter is good but will not turn the engine over when hot, check the engine for free rotation. Turn the engine over by moving the crank by hand (with the ignition off.) The engine could be sticking when hot and not be able to turn over.
The Ford Explorer service light will come on to tell you of a problem. The issue could be minor, or could result in loss of fuel economy, or cause engine failure over time.
Look over the entire engine for any loose parts. Listen to see where the noise is coming from. The noise could be anything from a loose bolt to an engine going bad.
Could be, Battery problem, Starter/solenoid problem, Battery cable connections/condition, Timing way advanced, Could use more info such as the year, make, engine and any modifications that have been done.
You could have a fuel pressure problem, lack of spark, malfunctioning computer, or internal engine damage.
1988 cougar will not crank over
Try locating and testing or changing the TPS (Throttle Position Sensor) Or if it's not in gear it could be the rev limiter keepin you from over revving & blowing your engine.
your engine could be seized or something mechanically locking the engine such as a dropped valve or some severe clutch damage