Calibrating the External MAP Sensor on my Haltech
 

When I got my Haltech Platinum, I lived in Colorado at approx 6000 feet above sea level. I had my Haltech tuned at that height, and it ran great. I have since moved to California, and done some basic retuning, but here's the question I have: does the external MAP sensor need to be recalibrated? If so, how? I'm have the Haltech Universal MAP sensor, pretty sure it is the 2 bar version.

Currently in the tuning screen, under the MAP sensor calibrations, with the engine turned off, but the key in the on position, the reading shows it is at 1.1 PSI. Because the engine is off, shouldn't it show 0.0 PSI (atmospheric pressure)? What are the PSI settings for the min voltage and the max voltage readings?

On my calibration window for MAP it says 0 = -28.6 and 5V= 30.7

Linear. It's weird that it's a little off for you. My car is at FP, so I can't see if mine is off calibration also...

Are you at sea level now? Maybe if you're below sea level (like New Orleans), it'd read a little higher? What did it use to show up in the mountains?

I never checked it up in the mountains, I let the tuner handle it all. For the 0 volts, it won't let me enter anything less than -14.5 And yes, I am at sea level now. Monterey, California.

External map sensors should come with the calibration data. Do you know exactly which one you have? Enter that into the external map sensor calibration, and you should not have to do anything else. The external map sensor will show atmospheric pressure when the car is off, not necessarily 0 - though 1.1 does sound a bit much.

It is the HAL 37100, the Haltech universal 2 bar MAP sensor, I checked to make sure. Where can I find the calibration data for it, I don't have it anymore, since it was about 1.5 years ago?

Dave

I can get the cal data for you Monday at the office.

Thanks, Hal, great service, as usual.

Ok, despite the thread title, may I ask why you just (didn't) don't use the 2 bar MAP sensor that is integrated into the unit? I believe it reads from -14.7 mmHg up to 29 psi.

Because I didn't want a vacuum line running into the passenger compartment. I wanted a short vacuum line to the external MAP sensor, and then electric lines form there to the Haltech.

Dave, I added the calibration data to the 37100 haltech 2 bar map sensor product listing for future reference.

0v = -14psi
4.707v = 14psi

Thanks, Hal

Put in those values, and my output with the engine off, but turned on is 0.1 PSI. That seems much more like it should be. Do some minor street tuning tomorrow before I eventually take it up to Z Car garage

Glad to hear that took care of it! :)