BlaCkPlaGUE

I know 'problems' that are associated with these sensors when they are out of adjustment/bad, but I still don't understand how they work in conjunction with each other.

-afm
-tps
-Pressure sensor
-Air temperature sensor

This is basic fuel injection 101, I know, and is probably way to broad to answer here. But if any of you have a link to a site that explains the following sensor and how they work together, that would be awesome.
I used to have this HUGE assed book on engines that would have easily explained it, but I havent found it now for months...

thx guys.

Kenteth

PV nerts!

PV=nRT

Pressure * Volume = moles * kR * Temp

what that means: Given the sensors, the ECU knows exactly how much air is getting stuffed in the engine. It can take the "air" and get the amount of expected 02 because we know whats in earths atmousphere.

Then the ECU knows how much 02 is going into the engine at any time, at any place, ect.

With this, it decides how much gas is efficient for a combustable mixture.

It only takes two variables to find the third, and effectively the entire set.

For example, you can find the vollume of air if you know the pressure and temperature.

Basicaly the ECU is using the pressure sensor and temp sensor, and volume(requires use of pressure, temp, and afm sensors) to find the moles of o2, which it mixes gas with.

Its not fuel inj 101, its chem 101... well, chem 112 actually

BlaCkPlaGUE

So, the temp sensor measures the density of the air, the afm measures the volume of the air, and the pressure sensor also calculates additional density of the air?

whats the tps for in this? fuel?

thx man, your making things clear already!

*edit*
what are moles?
what is KR?

Kenteth

kR= constant R
moles is equal to 6.023E23 molecules of an element.

Edit

constant r = gas constant r = .0821 litre atm / mole kelvin

mole = 6023000000000000000000 molecules of an element

BlaCkPlaGUE

So was I right?

Just a few other q's. When I open the flap afm with the car ideling, this causes the computer to think that a higher volume of air is present, will it add more fuel? or is that strictly only basesd on the tps sensor, and when the afm is open it can give the tps signal an idea of how much fuel to dump?

Gene

iTrader: (1)

It's everything together. At 50% throttle and 2000rpm, it's ingesting a lot less air than at 50% throttle at 7000rpm, likewise at 25% throttle and 2000rpm it's ingesting less air than at WOT and 2000rpm. It needs to know all the factors to calculate air useage properly.

BlaCkPlaGUE

I think the main reason I started this thread, was to find out how all these sensors work for troubleshooting purposes.

Like if I understood how each sensor worked in conjunction with one another, im sure that I could solve like 90% of any future FI questions I could have for the future. I could also help those that don't understand.

eh.. I really need to find that book