My 1990 corvette was running then I took it to a mechanic for a tune up and oil change he Put it on the hoist and now my corvette does not start no more.

Have you ever heard of the "mechanics rule" that says if it ain't broke don't fix it? Put the old coil and module back in they're not part of a tuneup because they can last for the life of the vehicle or not lol. I hope this helps. Take Care.

Someone probably dropped it in there some how. I couldn't think of a reason why. But you need to drain your coolant and put some new coolant in.

Corvette 1990-1996

After an oil change, or when "CHANGE OIL" appears on the Trip Monitor, with the ignition on and engine off, press the "ENG MET" button (located on trip monitor) once. Press the "ENG MET" button again within 5 seconds. Within 5 seconds, press and hold the "RANGE" button (1990-1994) or "GAUGES" button (1995). The light will flash. When it stops flashing and goes out, the system is reset.

Hope this helps and just keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer. Thank you for using FixYa.

Jose.

Chevy Corvette 1990-1996 Factory Service Workshop Repair Manual

Chevy Corvette 1990 1996 Factory Service Workshop repair manual...

Covers:Chevy Corvette 1990-1996

This manual contains all the necessary instructions needed for any repair your vehicle may require from bumper to bumper.
Whether its routine maintenance, such as tune-ups and brake service, or more extensive repairs involving engine and transmission disassembly. This file provides the most reliable information to perform the job.

Accurate, clear and concise text, combined with illustrations, make it possible for anyone with even a bit of basic mechanical knowledge to safely and easily service and repair their vehicle.

Comprehensive diagrams, in depth illustrations, and all the manufacturers specifications and technical information you will need is included.

Section included:

Tune-up and routine maintenance
General Engine overhaul
Automatic Transmission
Transfert Case
Driveline
Brakes
Suspension and Steering
Body
Chassis Electrical

Format: PDF - Download
Years:1990 1991 1992 1993 1994 1995 1996
Compatibility:any windows (95-98-ME-XP-7-MAC-LINUX-IPAD-IPHONE-IPOD)

may need a tune up but do a code reading with a OBTII reader to pinpoint more..

Mechanic time?

All I can do is suggest as my 'Vette's are older.

If my research is correct, I did find that the decklid latch mechanism is released by a cable. The cable probably has stuck in the cable sheath, due to years of neglect, (Failure to periodically lube the cable. Hint/hint)

You need to manually release the decklid mechanism.
Now bear with me, as again, my 'Vette's are older, ('70 and '76), and their seats tilt forward.

If you can tilt the passenger seat forward, perhaps you can get in there and lube this cable through it's sheath. (Use penetrating oil at first. I would then remove the cable, and clean it, then lube it, after getting the decklid open. Lube? White Lithium in a spray can)

Then try to pull the latch mechanism in the direction the cable would pull it, to release it.
(The cable may be broken?)

Yes! Whoever does this feat of magic, of getting to that decklid mechanism, will look like a contortionist! Hit the jacuzzi afterwards! lol!

first change plugs wires dist cap and rotor this tune up would be a good start

Do an oil change. When your ready to start it up crank it a few times before turning it over to assure the oil pressure is in the cam.
Naturally a new battery (thats the correct one.)
Clean cables.(including the wires off the starter and the starter interrupt relay)
Put a bottle of Injector cleaner in tank.
Replace coolant ,hoses and thermostat.
Bleed brake lines and replenish fluid then check calipers for leaks.
Replenish and blled out power steering fluid.
Change all ATF and Differential fluids whether
automatic or stick.
Inflate tires and be prepared for a rough ride until steel belt returns to normal.
After you got it to go, gonna take a while for radio to be normal again.
A/c problems are usually on the block of the high side pressure hoses.(You will see the oil film on the lines thats were the leak is.) This is all fun stuff any problems keep me posted I got an 81 thats all show I know what your going threw.

is it a security light that comes on? if so you may have a problem with the ign system. can you hear the fuel pump come on when the key is turned on?

we'll assume fuel is good..leaving spark and air..and management of systems(computer /sensors)...so the speedo cable was disconnected? try taking it loose again , test drive and report back please