MAP Question 3 Bar

[salvageV6]

Anyone know the voltage range of a 3 bar map sensor.

Is it like .2 to 4.7 volts scale, or .25 to 4.75 etc.

What's the published range of operation.


TIA

 

[ijames]

The GM maps are all 0-5V out so for a 3 bar sensor 0 volts = 0 bar and 5 V = 3 bar, while for a 2 bar sensor 0 V = 0 bar and 5 V = 2 bar.

 

[salvageV6]

Are you sure they hit the rails with the voltages?

 

[bruce]

I've never seen anything from GM listing the exact range.

But, I fired up my bench a put a meter on the MAP signal line.

20 K/Pa = 300 mv
300 K/Pa = 4.59v

I do recall reading it had an range of 20-300 K/Pa.

But, I don't run 9s so I shouldn't be taken, seriously.

 

[salvageV6]

I prefer real data to bench racing.

Not sure why anyone has to run 9's 10's or even 11's to fire up the voltmeter.

Thanks, I thought that might be the range very few electronics devices go rail to rail.

Gonna try the Motorola MPX series devices to build a good MAP device for about $25.

Start with a nice LED boost gauge first.

Just wanted to see if the range was the same or close to the GM device.

It is.

 

[bruce]

Originally posted by salvageV6
I
Start with a nice LED boost gauge first.
Just wanted to see if the range was the same or close to the GM device.

If you want some know points say 150 K/Pa, equal what voltage just tell me what you need.

 

[wagon]

http://www.kcsaab.com/aquamist/website/sl/plist/pics/mapm/mapm.html

http://www.kcsaab.com/aquamist/website/sl/plist/frm.html

This lists the 2 and 3 bar map voltage readings, it also shows a different brand with the same graph. Just click on the green check mark next to the item.

 

[bruce]

Originally posted by wagon
http://www.kcsaab.com/aquamist/website/sl/plist/pics/mapm/mapm.html

http://www.kcsaab.com/aquamist/website/sl/plist/frm.html

This lists the 2 and 3 bar map voltage readings, it also shows a different brand with the same graph. Just click on the green check mark next to the item.

Hmm, it lists the max output as 4.7, yet in the graph 300 K/Pa is 5v.

Since I don't run 9's, I'll let others ask the guestion, *How can that be?*.

It also doesn't jive with the min output spec..

 

[Razor]

Max output is 4.8 volts. 0 PSI is 1.6 approx. see the GM sensors all read a little different. Yes they do...

You cannot feed 5 volts and get 5 output. There is loss.

So its called a 0-5volt sensor when actually its not.

Want to duplicate a 3 bar, buy one and graph the results. Then match yours to that. Easy. And its only 29.4 PSI technically.

Its all a relative thing.

 

[salvageV6]

Buy one?

You gotta be kidding, WAY overpriced.

Not critical to my applications either.