1g maf on 2g ecu

[Specter]

Yeah very weird looking topic i know. Okay so the story is that i am unable to find the 2g maf so for time being in order to run my car i am using a 1g maf. My ecu is the evo III ecu, i have matched it from evo III ecu pinout diagrams and its exactly the same. I am told that i must be running the 2g maf. I have stock green top injectors.

So what is the engine experiencing when it is running on 1g maf. Its running 29-30% rich. What else is happening? How much more/less boost does the ecu reads then i am actually running? What happens to the fuel cut? Does it come early or does it not come at all? How aggressive are the fuel trims on this type of setup?

My car is running fine. Its rich of course. Other then that i am not able to hit fuel cut while dragging the car. It does hit fuel cut in neutral gear. And after certain rpm during dragging the car feels like its not going anywhere, like the engine has maxed out its hp and cannot throw any further and is asking for a gear change, but no fuel cut though.

Any help/theories appreciated.
Thanks

 

[jepherz]

What do you mean, 'what else is happening'? The MAF just measures the amount of air entering the throttle body. If you swap in a MAF that is incorrectly being compensated for, the ecu puts in different timing and fuel. That's it.

 

[grocery_getter]

For the same amount of voltage being feedback to the ecu, you are running less air.

Watch out. Constantly running richer, although not as deadly as running leaner, can also contribute to a lot of problem down the road.

 

Since the airflow signal at WOT is 25-30% higher than it should be, you are going to be 25-30% too rich, you are going to hit fuelcut 25% sooner, and you are going to run up through the maps 25-30% faster, which means you will be using much richer maps with a lot less timing advance than you should have, which is going to make the exhaust gasses very hot. I'll bet your exhaust manifold is glowing red after a run. Very bad for your car, get the proper 2G-type MAS!

 

[Specter]

Hmm, it is running richer, yes, but i am not hitting fuel cut. What could be the reason? Exhaust gasses are hot after a run but not that hot that the manifold glows. Or maybe i am not giving it enough runs to do that. I just wanted to know about the fuel cut.