RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   How does ECU calculate fuel/timing cells? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/how-does-ecu-calculate-fuel-timing-cells-913509/)

soldave 07-17-10 05:41 PM

How does ECU calculate fuel/timing cells?
 
Just curious about this one. I know the ECU will probably use rpm on the horizontal axis of its timing and fuel maps, but what does it use for "load"? I'm guessing it's either airflow (calculated through the airflow meter, maybe measured in g/rev or similar) or manifold pressure, detected by the pressure sensor.

If it's the latter then it would mean that if your pressure sensor isn't reporting the right voltages, your timing and fuel maps could be way out when you're driving, right?

SirCygnus 07-17-10 07:32 PM

its a combination of everything.

jjcobm 07-17-10 08:16 PM

It uses a lots of mathematical formulas taking in considerations all your sensors (i.e. coolant temperature, crank angle, air temp, AFM, MAP, ect.) to compensate for the different conditions you are driving in. And it does this all very quickly with minimal lag....


Originally Posted by soldave (Post 10115108)
If it's the latter then it would mean that if your pressure sensor isn't reporting the right voltages, your timing and fuel maps could be way out when you're driving, right?

Well, not necessarily only the pressure sensor, but anything that is not working will effect driveability in the ECU. That is why it will freak out and give you a check engine light because it will not run optimally and will revert to "safe" map values so you don't kill the engine.

HAILERS 07-17-10 09:54 PM

1 Attachment(s)
HENRIK and TURBO2LT created the RTEK 2.0. In the past they have made threads on this site and answered threads on this site about the question you asked in this thread.

Sooooo, if one does an ADVANCED SEARCH and throw in either of those two names OR NZCONVERTIBLE, you will find some of your answers and more. As an example I put in HENRIK and LOAD and got at least ten pages of hits.

One of the threads included what you see in the attached jpg. A post from NZCONVERTIBLE about some topic close to what you asked.

Usually the hits will high lite the name you put in. Like HENRIK will be highlited in RED in the thread somewhere.

Or your search could include HENRIK and PRESSURE SENSOR or BOOST SENSOR. You name it and you'll be bound to find something of interest.

I can't attach the jpg right now. I'll try later. Personally I don't know dog about your question. I just drive the car and that's good enough for me.

soldave 07-18-10 03:35 AM

Thanks for that. Will check out those posts :)

HAILERS 07-18-10 09:46 AM

I mis-spelt a name. That is TURBO2LTR


All times are GMT -5. The time now is 07:14 PM.


© 2024 MH Sub I, LLC dba Internet Brands