can't get Chevy Blazer heater to work

[carriedi]

do you have spark the whole time you are cranking? or does the spark disappear too?

you should use a scanner and verify you are getting a cam and crank sensor signal

[j4ml3]

It has spark the whole time it will run on ether. I have scanned it with obd2 reader and there are no codes no check engine lights

[carriedi]

might have to use a graphing multimeter or a lab scope and see what is happening with the signals that control your fuel injector pulse.