Help start my mkiii
 

I have an 87 turbo supra and it wont start it cranks and goes on for 1 or 2 seconds and then it shuts off. I have changed the igniter, ignition coils, ecu, fuel pump and filter i have checked all the fuel lines, all fueses are good and i have spark and gas. Could anyone help????? its been down for a month already and it sucks not being able to drive it.

It actually stops cranking altogether? Most likely overheating wiring, starter, starter solenoid or relay.

It cranks then it starts but it wont stay on. is there a way to check the relay?

Any diagnostic codes? There are a LOT of possibilities and if there are any diagnostic codes stored it may help a lot. Providing more complete information on your part will help too. ;) Does this happen when the engine is completely cold or when it's hot or it doesn't matter what temp; does the car run find the rest of the time; is it smoking, does the exhaust smell of excessive fuel; when did you last replace the plug wires, spark plugs and distributor/rotor; is this a 7M-GTE or 7M-GE or something else?

it hasnt started at all but when i try starting it, i smell gas. there are no codes anymore it was code 14 first but i changed the fuel pump and it went away. it is a 7mgte i just changed the plugs but not the wires and im not sure about the distributor i dont know if it works or not and its kind of expensive to just go out to buy one.

So you've just checked for codes? Because code 14 has absolutely nothing to do with the fuel system and it isn't going to go away by itself. As I'm sure you've already read it indicates a bad igniter, coils or ECU. Intermittent operation is quite common when these go out but typically you'd also be seeing problems while the engine is running.

Did you change the fuel filter when you changed the pump?

The 7M-GTE doesn't use a distributor... but you do have a CPS and multiple ignition coils which may fail.

Does engine temperature affect this problem?

I would start with checking cables, battery voltage (unlikely culprit but worth checking), ground point (especially for the igniter and coil pack), test the igniter and coils as shown in the TSRM.