Map Sensor Help - Tuning Forum

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Map Sensor Help
Tuesday, January 12, 2010 4:54 PM
Ive been looking for some sort of map sensor pressure/voltage tables.

Looking for 2 bar and the 3 bar, already have the 1 bar.

Want to see how the voltages change with the different pressures.

Im working on something that will be useful for people that want to do some tuning WITHOUT HPT. This will allow for different injectors and different Map sensors......

Thanks in advance.
Thomas

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"


Re: Map Sensor Help
Tuesday, January 12, 2010 4:55 PM
Thomas

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

Re: Map Sensor Help
Tuesday, January 12, 2010 6:09 PM
how? map sensor doesn't control injectors





Re: Map Sensor Help
Wednesday, January 13, 2010 3:31 AM
DaFlyinSkwirl (Pj) v2.0 wrote:how? map sensor doesn't control injectors


Sounds to me like a good way to get rid of an extra engine that's just laying around. Everyone has one of those.





i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
Re: Map Sensor Help
Wednesday, January 13, 2010 4:15 AM
once I get the info I need and get it tested, I will explain more how it will work.

anyone have any information that will help?

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

Re: Map Sensor Help
Wednesday, January 13, 2010 10:39 AM
Courtesy of How to Tune and Modify Engine Management Systems by Jeff Hartman (Page 38).
Quote:


Load Percentage___MAP Voltage__1-BAR (kPa)__2-BAR (kPa)__3-bar (kPa)
_____0______________0.00_________10__________8.8_________3.6
_____5______________0.25_________15__________18__________17
____10______________0.50_________20__________28__________33
____15______________0.75_________24__________38__________48
____20______________1.00_________29__________48__________64
____25______________1.25_________34__________58__________80
____30______________1.50_________39__________68__________96
____35______________1.75_________43__________78__________111
____40______________2.00_________48__________88__________127
____45______________2.25_________53__________98__________143
____50______________2.50_________58_________108__________159
____55______________2.75_________62_________118__________174
____60______________3.00_________67_________128__________190
____65______________3.25_________72_________138__________206
____70______________3.50_________77_________148__________222
____75______________3.75_________81_________158__________237
____80______________4.00_________86_________168__________253
____85______________4.25_________91_________178__________269
____90______________4.50_________96_________188__________285
____95______________4.75________100_________198__________300
___100______________5.00________105_________208__________315


I probably didn't need to give you every value, considering map sensors are almost perfectly linear...but there you have it anyways. Like the others said though, unless you are making a standalone driver for the injectors, there is nothing you can do to control them on an Alpha-N PCM. This is why back in the day, people couldn't understand why their SAFC-2 wasn't working for them. On the other-hand, if you are doing something for a supercharger reflashed or 97' PCM (both of which are speed density) then you should be able to piggy-back a circuit to fool the PCM (e.g. SAFC-2)...which is a poor solution to your tuning woes in my opinion.




I have no signiture
Re: Map Sensor Help
Wednesday, January 13, 2010 5:20 PM
Maybe part of thinking is a little off.

the ecu uses tps vs rpm to select the fuel table, doesn't it reference map as well? if not, why would it matter what bar sensor is used?

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

Re: Map Sensor Help
Wednesday, January 13, 2010 6:08 PM
Fueling scheme is Alpha-N (TPS vs. RPM). The map sensor is there for spark table(s). So, if you use the wrong map sensor, you can see that the PCM will references the wrong spark bin, and instead of maybe 30 degrees of advance at WOT you might be running closer to 45 degrees, which is extremely dangerous to your engine.

I believe the map sensor is also referenced for shift points and/or shift firmness on automatics...not positive on that though. I'll take a look through the 4t40e documents I have and get back on that one.




I have no signiture
Re: Map Sensor Help
Wednesday, January 13, 2010 6:31 PM
no auto here so no worries.

I believe I have what I need for now. Does the site you listed also have the voltages for the tps? I have one in my paperwork from my dsm just not 100% sure if they are the same, they are both 5v sensors

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

Re: Map Sensor Help
Wednesday, January 13, 2010 7:05 PM
Here we go again.........





P&P Tuning
420.5whp / 359.8wtq

Re: Map Sensor Help
Wednesday, January 13, 2010 7:05 PM
DSMskyline wrote:no auto here so no worries.

I believe I have what I need for now. Does the site you listed also have the voltages for the tps? I have one in my paperwork from my dsm just not 100% sure if they are the same, they are both 5v sensors

It's not a site. It's a book. But no, it doesn't list anything.

I can tell you though, that the TPS is nothing more than a potentiometer (variable resistor) that reads between 0-5V, which means that throttle percentage will be linear.




I have no signiture

Re: Map Sensor Help
Wednesday, January 13, 2010 9:16 PM
Whalesac wrote:
It's not a site. It's a book. But no, it doesn't list anything.


Sorry, was on my phone earlier and it looked like a link... Didn't see the page number at the end.

Whalesac wrote: I can tell you though, that the TPS is nothing more than a potentiometer (variable resistor) that reads between 0-5V, which means that throttle percentage will be linear.


Yeah I know how they work, I also know that it will never see 0v nor will it ever see 5v. Ive seen some where full throttle is only like 3.5v. Ill do some more digging around to see what I can find.

I do greatly appreciate the help.

One thing I don't understand is why people complain that there aren't many options for things for the J-Body platform but then they turn around and talk crap when someone asks a question for clarification when trying to make something.... Makes no sense to me.

Thomas

"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

Re: Map Sensor Help
Wednesday, January 13, 2010 10:27 PM
I still don't know what you intend to do with all of this info, but why not just measure the output voltage of the TPS with a simple multimeter at 0% and 100% and knowing that this is a linear device, interpolate the values in between? ... It's simple, quick and plenty accurate. In fact, that's exactly how us megasquirt guys/gals calibrate our throttle gauge. Well, anyways, good luck with whatever you plan on doing with this.




I have no signiture
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