M5 won't start after sitting 2 years

[fatebender]

Car has been sitting in storage for 2 years, engine was running perfectly before hand but I can't get it to fire up now. The starter cranks but no sign of life from engine.

So far i've installed a new battery, fresh fuel/coolant/oil, took out the spark plugs put some oil in cylinders and made sure engine turned over freely by hand, and did an ews sync through INPA.

It has a new fuel pump from just before it went into storage, all cps/crankshaft sensors fairly new, and it's not pulling any new error codes.
I can hear the fuel pump prime when turning key and it smells like fuel after cranking a few times.

Fuel? Spark? Compression? DME? What could go wrong just from non-use for a couple of years? Not sure which is most likely, learning as I go here, any ideas?

[JimLev]

Start by checking for fuel pressure at the rail, then spark at the plugs.
Report back.

[edjack]

Scan for codes before you report back.

The E39 can "lock up" after setting for two years. I assume you did not put a battery tender on it. Thus, the battery slowly died.

Try a reboot:

Battery slowly dying and weird results

There is some anecdotal evidence that suggests that, when the battery slowly dies, the various electronic modules enter an undefined state.

Ensure that the battery is fully charged. Wake the car up (open the boot) and let it go to sleep (16 min). Disconnect the negative terminal of the battery and let the car set for an hour or so. Reconnect, and observe the results.

Report back.

BTW, do you know that the car wakes up every minute to measure the temperature? As the battery dies, who knows what the car may be thinking when it wakes up to a dying battery?

[fatebender]

Thanks for the suggestions, got the car started this afternoon. When I went to check if there was spark at the plugs I just decided to put some new ones in. Tested one and saw spark so gave it a few cranks and it fired up. Old ones were soaked in fuel so maybe engine was flooded.

Good feeling when the engine comes to life.