It doesn't seem to me that my block heater is working as good as it did last year, so I checked the resistance across the prongs on the cord coming from the heater and get a reading of 19.5 and I had read somewhere where it should be 18. Can anyone tell me if the difference in the readings could indicate a problem or is 19.5 ok and I'm imagining it isn't working as good? Also would anyone have any idea what temperature the block heater keeps the water at....justs curious.
Thanks for any help....

 

You might follow the cord and make sure the connection is clean and tight.

18ohm and 19.5ohm is close IMHO, close enough that the heating element isn't blown IMHO.

 

Before I installed my cord I ohmed the heater itself and it was 19.5 ohms. New truck.

 

Thanks guys for getting back with me....I'll look a little closer at it when I get just a little more time but it sounds to me like it may just be my imagination... which is good you probably saved me some money and time.
Thanks again,
reflog

 

I've noticed the exact same thing!