MAP sensor issue... newb... sorry

TomsEJ1 · Post by **TomsEJ1** » Wed Aug 12, 2009 10:15 am

ok so i just got ectune with a demon board. my car: 95 civic ex with LS/V high compression. i started to data log yesterday to get some ides on getting a good base tune when i noticed at full throttle the map sensor is reading -3.07. so i went home and checked everything. even used another sensor i had laying around, same results, KOEO its the same reading. i have not thrown a code in this car ever. wiring harness is virgin and the ecu is a xenocron chipped P06 vtec converted. im new to the tuning world and i have searched for about 6 hours. any help would be great. thanks Tom P.S. if you need anymore info just ask.

Orthello · Post by **Orthello** » Wed Aug 12, 2009 10:28 am

What woltage does is show in the logger in both: car running idle and KOEO?

TomsEJ1 · Post by **TomsEJ1** » Wed Aug 12, 2009 10:38 am

At 6600rpms 103% throttle the map is at -3.29psi and 2.29V. KOEO its at -2.97psi and 2.35V

TomsEJ1 · Post by **TomsEJ1** » Wed Aug 12, 2009 11:48 am

sorry i misread your question. engine at ldle: 755rpm, MAP: -11.23psi, 0.82V

Orthello · Post by **Orthello** » Wed Aug 12, 2009 1:38 pm

TomsEJ1 wrote:sorry i misread your question. engine at ldle: 755rpm, MAP: -11.23psi, 0.82V

I don't see the problem. This is exactly what it should be. What where you expecting to see? Try playing around with: 'Settings' and click the 'Units' tab. Play there with the Vacuum settings.

TomsEJ1 · Post by **TomsEJ1** » Wed Aug 12, 2009 1:50 pm

at full throttle its not at zero. its at -3.07

Orthello · Post by **Orthello** » Wed Aug 12, 2009 1:51 pm

yes... because it can not reach the exact athmospheric presure @ WOT. Ther still is no problem dude. Engine is behaving just normal?! AFR are normal?!

TomsEJ1 · Post by **TomsEJ1** » Wed Aug 12, 2009 2:06 pm

yes engine is preforming normal, afr is within range at WOT. so do i tune for that collum in the program?

Orthello · Post by **Orthello** » Wed Aug 12, 2009 2:53 pm

What were you expectingto read for MAP? Why did you conclude that you MAP sensor was failing?!

TomsEJ1 · Post by **TomsEJ1** » Wed Aug 12, 2009 3:16 pm

i was under the impression that it should read closer to zero. the scolars on ectune go to 0.44 and im not sure if the MAP sensor is failing thats why i was asking.

98vtec · Post by **98vtec** » Wed Aug 12, 2009 11:24 pm

it will only read as high as atmospheric pressure (NA) unless your engine is very efficient and has a VE above 100%. you are in colorado. Your elevation is likely pretty high. The higher you go, the lower the atmospheric pressure, and the lower the map will read in the program. You tune the columns the engine sees.

TomsEJ1 · Post by **TomsEJ1** » Thu Aug 13, 2009 12:36 pm

ok thank you thats what i needed to know. i was all confused and thought somethng was wrong with my motor, i didnt even think about my elevation. which is 6200FT ASL.

thething96 · Post by **thething96** » Fri Aug 14, 2009 1:54 pm

I'm in the Chicagoland area, my n/a map values at full throttle were -0.46 or so.......

jpjackson · Post by **jpjackson** » Tue Feb 09, 2010 3:46 pm

select inhg gauge in the settings/units. not inhg, that is what is giving the negative value.

ckretvix · Post by **ckretvix** » Tue Feb 09, 2010 6:45 pm

Try starting a new map. I had an issue with my TPS and MAP reading strange voltages and a fresh file fixed it.