I put my code reader on my truck and all it will show is ERROR thats it could someone please help and tell why would be showing that reading .

What is the obd plug ?

Hello pushrod I have a 1997 dodge ram with a 3.9 engine and I have replace the fuel pump the spark plugs the cam and crankshaft sensor and it just will not start it trys to but ijust will not also ive replace coil so there is really not to much that I havent replace I just at my witts end with my truck but iam not going to give upcause I know I will firque it out hopefully with your help

Test for spark 'in this order' > Pull coil wire *from* the distributor cap, test for good hot blue spark from coil wire to a metal surface (ground) as helper cranks engine. .. 'IF' spark is HOT, put coil wire back in dist cap then check spark from a plug wire, should be the SAME hot blue spark!! .. Now, 'IF' spark is HOT from the spark plug wire just like it was from coil wire, spark test is pretty much complete! .. Now, carefully spray a little carburetor cleaner into throttle body and try to start engine .. 'IF' engine temporarily starts then dies .. problem is fuel related ... 'IF' you are unfamiliar with ANY of these suggestions and unsure how to perform them safely... Seek qualified hands-on help!! .. (Don't know your skill level) .. Post test results for more info.