Yeah.. I highly doubt that there is enough fuel pressure to force the injectors to inject too much only in a certain rpm range. But if you get those logs then we can start narrowing it down.

I have another test for you to do once you get things squared away that I found interesting with my car.

 

The ECU will compensate that, wouldn't it?

 

I think I am going to get a z06 vet after this is fixed. I'm probly fix this issue and sell this thing...Or get factory 5 racing's; project 818

 

Haha it's a fun car when it's running right. I don't think this problem is too tough, it's just gonna take looking at it from a different point of view.

 

I know i'm just getting frustrated. I have no patience for this ****. I normally do have this kind of issue diagnosing a problem.

 

Trust me, I know exactly how you feel...

What all reasons could a car be going rich at a certain rpm?

Is the car going rich causing a lack of power and that causing the low MAF readings, or is airflow down causing it to go rich and then lose power?

If the MAF reading is lower than it should be when the car goes open loop, it should only provide enough fuel for the air it sees anyways, right?

What other things does the ECU look at for fueling in open loop besides rpm, MAF, baro, intake temp, and...?


Just trying to go through the list

 

o2 sensor, crank sensor, knock,....

 

O2 sensor isn't looked at during open-loop, the crank sensor is only used for ignition timing(well and injector timing but that shouldn't matter too much) and the knock sensor is only used to pull ignition timing as well...

 

So there's only three things going on that can cause anything to happen, that's air, fuel, and spark.

Air is pretty much ruled out because our MAFs work, my intake temp and baro sensors work(i assume yours do as well), intake valving are working correctly, and unless both of us have a vacuum leak we can't find, then that's fine too. Looking on the other end of things, excess backpressure could cause issues as well... but I don't have a cat, so that isn't it, and the muffler idea I had is VERY unlikely.

Fuel is unlikely given that we are going rich and there aren't many ways that can happen... and you got your injectors tested, so that's not the issue. Excess fuel pressure shouldn't matter because the injectors will take care of that and the FPR is pretty foolproof on these. And a leaking one would pose more issues at idle than high rpm.

Spark shouldn't be the issue because coils, plugs, wires are all good and the timing should be correct and the ECU should throw a code of it isn't.

Which out of those things are most likely and testable?

 

Even though I checked the ect it still could be the issue. It can cause extreme rich mixtures..... Now last night I took the back seat bottom out and found that the fuel line from the fuel pump housing is leaking. Really bad, plus when I start driving it goes away. Which makes me wonder if my fuel pump isn't giving out after I start driving .
Still didn't get those data logs yet we forgot the tuning laptop at house. I was messing with a friend wrx at lunch time yesterday.

 

How exactly would the ECT have an effect on that? I just don't know enough about what that controls to diagnose that.

If the elbow for the fuel line is cracked, then it's a pain to fix and you'll end up getting a new fuel pump housing, which you might as well get a new pump at the same time.

Wouldn't fuel leaking cause a lean condition though?