1989 Buick Park Avenue Non-starting

Our Buick Electra Park Avenue has developed a non-starting problem. It will crank and crank and never give any sign of starting.

This started as an intermittent problem and you could eventually get the car to start.

The fuel pump and filter have been replaced.
The camshaft and crankshaft sensors have been replaced.
The main computer has been replaced.
The spark plugs have been replaced.
The Idle Air Control Valve has been replaced.
The ignition control module has been swapped-out for a known working one.
The coil packs were swapped out for new ones.
The plug wires were checked.

Only on occasion will you ever smell any gas fumes when trying to start the car.

Back when you could get it to start, it would crank and crank and not even attempt to fire up, but once it decided to try to start, it would start immediately as it always had.

This car has no remote entry but for quite some time has had a habit of unlocking itself, the trunk popping open at random or the alarm going off at random. People who sell security bypass kits tell me this is not an issue with this car.

My mechanic tells me that there is spark and compression and air and fuel.

The starter is a beast - I drained a full battery the last time I tried to start it.

It still runs great when it will start.

Any and all advice would be appreciated.

Thank you,
Jim