Hello I need help with a pretty serious issue. Recently I bought a 1996 850GLT and the engine had a knock on the bottom. I decided to make this a car for my son so I changed out the engine. The replacement engine had 90K miles on it and it came out of a car with an airpump. I changed over all the external engine components from the old engine to th enew engine. I also replaced the oil seal on the crank, timing belt, spark plugs, rotor, distributor cap, and the spark plug wires.

The engine turns over nicely, has great compression, but will not start. The timing of the crank and camshafts has been checked an rechecked. When I first start to crank it, it will attempt to start once or twice then nothing. I remove the spark plugs and they are wet. I let them dry, put them back in and the whole cycle starts over again. The spark plugs are getting spark, it is almost like the spark is being drowned by fuel, or for some reason the firing is stopping. I currently have the car at a repair shop and they are still lost on this problem.

Does anyone have any idea what could be causing this problem?

I would appreciate your guidance on this. Thanks

Check for excessive fuel pressure, badly leaking injectors, and bad or disconnected engine coolant temp sensor - all of which could cause dousing with excessive fuel.

Will the car start and run for a bit if you floor the throttle while starting (which if throttle position switch is ok will stop the injectors supposedly to clear a flooded condition)?

Another test is to disconnect the mass air flow sensor - the engine should revert to a nominal or default mixture. If this starts the car then the MAF or its wiring may be bad.

You may need a camm position sensor.

cam sensor could be the problem, wrong timing of the spark.
Also you could have a weak spark, could be A bad coil, or powerstage.