when i start my car my fuel pressure gauge which is electronic reads about 38 after as couple secs it drops to 20ish. i put a new pump in it (walbro) it stays at 20 even when i rev it up. is it possible the gauge is misreading or the adj regulator not working right?

 

Need to check it with a mechanical gauge. What brand is the electric gauge - analog or digital?

 

autometer and analog

 

You need to check it with a mechanical gauge. About $35 from most any parts store.