I'm experiencing an odd issue with my brand new AEM 5Bar map sensor that is just irritating to me. For starters its seeing about 2psig with the car turned off (atmospheric pressure). Also it seems as though the gain is off as well when I compare the voltage output to my manual boost/ vacuum gage. I can go in the EMS and setup the sensor manually gain / offset to compensate for this but when I called AEM they advised against it. AEM also suggested I double check my ground I did and bench tested the sensor off the car and both times the issue remained. If this is off by a decent amount my guess is it will throw off the boost fuel compensation. Has anyone else experienced this? Any help would be really appreciated.

 

make sure the sensor inlet is pointing down towards the ground and not sideways or upside down

 

My sensor was always slightly off on AEM Series 1 and when I switched to Series 2 it was almost on the money. I tuned with that in mind all the time on Series 1.

AEM says Series 2 reads different and I should trust it over Series 1. As long as the car is tuned properly you'll never have a real problem if its slightly off.

 

Out of curiosity how far off was it? Mine was also out of cal on a bench test as well.



I tried several positions and it never seemed to change.

 

-1.9 to -2.1 average. Now on Series 2 its -0.6 while the car is not running but key on.

 

ok Thanks. You don’t' happen to know what voltage you were seeing at the sensor series 1 or 2? I'm at about 1.5 volts

 

i had one in my manifold upside down. filled up with oil and i had to trash it. got a new on about 500 miles ago and installed it point down like petey said. was all good till last night i noticed it has reading +2psig engine off. but when i start the engine and go wot at low rpm it goes to 0. i think its a slight voltage or ground issue. or aem sensors arnt made that well, or both.

 

From my understanding they will be off a little due to different elevations having different air pressures. Mines a little off too, but not as much as yours.

Also try having the car running and put the vacuum line and seeing what the reading is.