Testing my assembly. Is 100KPa with no hose attached correct

jaykvb · Post by **jaykvb** » Sun Jun 28, 2009 7:26 am

Ok. I built the kit today and all seems to work ok.

Except I have one question which I am hoping is a stupid one.

If the MJ with MAP sensor is powered up on a bench and connected to my computer. What should the Load be measuring. My unit is reading 100Kpa with no vacuum applied... If I attach a hose and give it a suck the dial goes backward to around towards zero and defaults to 100 with no vacuum.

Is this the correct operation or is the load meant to go from 0 towards 100 when vacuum is appled. Have I stuffed my assembly?

Rdgs John

cng1 · Post by **cng1** » Sun Jun 28, 2009 12:55 pm

That sounds entirely correct. 100kpa is what we see around us all the time, with the engine sucking against a closed throttle that will drop down to something like 30 kpa. On a forced induction engine you will see numbers above 100kpa when you are "on boost".

jaykvb · Post by **jaykvb** » Sun Jun 28, 2009 11:44 pm

Great.. I was hoping it was going to be a stupid question.

It shows my lack of understanding of Kpa, but if you don't ask you may never find out.

Thanks...

John.