Brenner does not heat correctly.... ????

Hi together...

after I get my hour. I've bought a new battery, there's plenty of power, but the burner is not going 100% yet... Somehow, when it's switched on, it's kind of detonating, there's a little bang and so on. Then he's running... but only a short time, then he goes out again.... Is there the glow plug defective and how / where can I fix it?

Winter greetings...

Alex