Hi! What line of code should i remove in order to just show boost? I currently have a diesel turbo suv and I don't need to indicate the vacuum on the gauge. Thanks! Btw subbed as well. Really helpful videos. Will start soon hopefully on this project!
Hi pistoplat_, I used a MAP sensor, so it gives absolute pressure and it is a bit difficult with that one to read boost, although not entirely impossible. If you have a similar one, you can do something like if pressure < 0 then display 0, anything above 0 can be displayed. It is not entirely boost, as boost is the pressure above atmospheric, which changes depending on weather. Check out my other video for measuring crankcase pressure (ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-h4TQ-XVWU30.html), that one uses relative pressure and will display actual boost over atmospheric pressure.
@@moremolecules oh wow i see. So basically, in theory, using a map sensor can be used in all boosted vehicles and it can be programmed to show or not show vacuum as well. This is very cool and useful :D. Is there any chance it would be fine to contact you personally for more questions in regards to the topic? :)
@@pistolpat_5547 Yes, but for boost the MAP sensor will not be that accurate as you do not exactly know the atmospheric pressure. Say you think the atmospheric pressure is 1,000mbar, but it is 970, the final measurement will be off by this difference. If you go onto the channel's about there is an e-mail there.
@@FluxApex Yes, I have subsequently used a differential pressure sensor for say crankcase pressure. It has two spouts/inputs, one atmospheric another for the crankcase pressure. I used a DPF exhaust pressure sensor, much easier than with a MAP. This was just a video to show how to use the MAP, but I have not used it afterwards. Something like this here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-h4TQ-XVWU30.html
Use the "map" function in the Arduino to do this. Then you get more accurate reading too. This give you 1024 steps betwen 20 and 250kPa, not 870 steps (82 - 952).
I do not quite remember why I did not use the map function in this case. Either way the range would not be different as the values returned were bound by the voltage, which was not 0-5V.
Hi Rob, pure luck, I was googleing the numbers on the MAP sensor and it came from Bosch. I think most will be the same pinout. Some pinouts can be found here as well (partsbos.com).
@@moremolecules yes i try to fix the formula with athores numbers and dont work. my map sensor is mpx4250ap. so the numbers is Vin=5,1v the MIN 20kPa is 0,2v and the MAX 250kPa with 4,9v. you made a video that you explain so well but i cant find solution. this formula work with all map sensors?
@@sodomakgomora2995 The code should work with any MAP sensor. The relationship betwee the min and max is linear, so if pluging the numbers in the formula should lead to correct results. Why do you need bar instead of mbars? What happens if Pabs=Pabs/1000? Does this give you bar?
@@moremolecules first of all a big thumbs up that there are people like you and they helped us in the best way. sorry about my english... google translate :P and yes work at bar but i just at the code remove at the calculator 1 bar (the atmosphere presure) to see the difference and show me presure at my turbo like all the gauges. mate you are great keep that. now i buy new one presure sensor with 2 intake to set the true presure of my turbo :)
@@sodomakgomora2995 Yes, the MAP is absolute pressure and the one with the 2 things is relative. If you leave one open it will show the difference with the atmospheric pressure. Good luck
