I have a 02 monte carlo. I had some overheating issueso and had to replace my radiator and also replaced the head gaskets and when I got the engine back together. The car now won't start. It cranks but nothing else. I have fuel it seems to have good compression. Any help will help

 

Does it have spark?
Sounds like something got missed in the reassembly. You may want to back track your reassembly steps and see if a wire didn't get put back right. It happens to the best of us. Lol

 

Yes it has spark and we have checked all the wires and everything we took off went back together

 

Air, spark and fuel are the magic formula. Are you sure all the plug wire got put back in the right order? If it cranks you can rule out PCM or anti-theft/ ignition problems.

 

Check the wire harness to your ignition module!

 

If you crank (as Plumbob said, rules out anti-theft and dead battery), you validated compression and spark. I assume no blocked air intake... Next, do you know that you have fuel pressure? Can you hear the pump hum when it primes?