The furnace typically takes three or four ignition cycles before flame extends down burner to reach the flame sensor. It seems to light only halfway down burner on most attempts. Sometimes reaches shut off and then I have to flick switch to repeat cycle. Help.

If I understand you correctly, all the burners need pulled and cleaned. Sometimes rust or a spiders web gets in the little crevice at the end of the burners keeping it from extending the flame to the next burner.

Thanks. Will give it a try.

The furnace typically takes three or four ignition cycles before flame extends down burner to reach the flame sensor. It seems to light only halfway down burner on most attempts. Sometimes reaches shut off and then I have to flick switch to repeat cycle. Help.
Works like a charm. Thanks again.