Unless there is something weird going on you should just enter the linear and offset for the sensor and leave it alone. Maybe a slight tweak on the offset, but only a small amount. If the numbers I gave you don’t seem reasonable, you need to rig something up to apply a known pressure and measure voltage to calculate the linear/offset.
Okay, this is what I came up with.
@0 psi 1.58v
@4 psi 1.78v
@5 psi 1.84v
@8 psi 1.99v
How was this measured? I assume this is gauge pressure not absolute pressure? If gauge pressure, need the barometric pressure for your area. Can get it from a weather app.
It's 30.2 inches HgOriginally Posted by gtstorey
This is only as accurate as the numbers you posted.
Linear is 97.55psi per 5v
Offset is -16.00
Well, I guess that won't work. The lowest setting HP Tuners will allow on Offset is 0.
As a last ditch effort, I bought another 12615136 and made sure it was an ACDelco. I installed it and put the Linear and offset back to 200 and 7.99. Now it seems to be staying in spec at both ends and the car seems to be running better. Before buying this sensor, I did a lot of research and found out that almost all of these sensors are listed as either a replacement for each other or for one that is no longer made. While looking through the specs I found some are listed with different specs for the same part number and were advertised as 2, 2.5, and 3 bar. What a nightmare this has been, I now doubt half the people out there even have a MAP sensor that is correct and working properly anymore.
Thank you for everyone's help with this.
It would be interesting to see what values you come up with using the same test procedure that produced your values in post #22. But at least I feel better that my original math worked. Trying to work off cross referenced data can be a little tricky.
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