[agent008]

You guys do have a high ethanol content in your fuel down there don't ya?

Yes, regular is 27% and premium is 25% ( premium is higher octane due to a better base gasoline being used for the mix, not due to ethanol content. Regular is crappy base gas mixed with ethanol which improves the final octane)

Ia have been running on regular since I got the car last year. Previous owner ran it on premium so I got the lean code twice (just don't remember if it was P0171, think it was another code) due to a short term fuel trim being adjusted more than threshold when I filled up with regular for the first time. After clearing that code twice I never had any codes again. CAI went in, and P0171 started appearing. So I don't have much reason to suspect fuel. Just thought the CAI being a bit different in shape and diameter might be throwing the MAF sensor off a bit, and tried filling up with premium to check whether the P0171 code would go away. But it came back.

 

[JohnWR]

@agent008 : You may have a stack-up of inconsistencies working against you. The MAF housing you are using is 4% larger than stock, so you are getting more air than expected, your fuel is more oxygenated than the system is designed for, and your intake being a different shape probably has some effect, but there is no way outside of a flowbench to know.

Putting everything back to stock temporarily would tell you whether the MAF sensor is working properly.

 

[agent008]

Thanks @JohnWR , I am 99% sure my problem is the CAI. No codes before.
But still, before I ditch it altogether, I'll pull the MAF sensor out and check for oil. If it passes this test, I'll try to improve the CAI (check for leaks) and give it a second chance.
I'll be updating my progress when I can make some time for it. Probably later along the week and on the weekend.

Have a great week folks!

 

[ennonne]

Yikes, 25-27% Ethanol. That's definitely affecting things. E25 stoichiometric air fuel ratio is around 13:1, where pure gas is 14.6:1, so the control system is having to add about 11% more fuel to compensate. Put another way, it "thinks" it's 11% lean, just due to the fuel. That eats up a good chunk of the distance to the threshold that it's looking for to set a 171 lean code. Wouldn't surprise me one bit if your new airmeter setup is reading a bit low. Do you have a device too look at OBDII data? Looking at the fuel trim will show you exactly what's going on. Putting the stock setup back on will tell you if your setup is working or not. Code typically sets around 25 to 30%

A little bit about the meter. Yes the diameter of the tube it's inserted into has a great affect on the airflow reading, but it's more than the diameter. What is happening to the airflow ahead (and after to a smaller extent) affects the reading too. I have personally flowed the same airmeter, in the same tube with different air filters on the end. I saw a total variation of more than 30%. The best analogy for what an airmeter is doing that I could quickly come up with is to try to measure how many people are leaving a stadium by measuring the number of people coming out one door. LOTS of factors that affect the numbers you'd get. Airmeter is doing the same thing, sampling a very small amount of flow and inferring total flow.

 

[JohnWR]

Thanks @JohnWR , I am 99% sure my problem is the CAI. No codes before.
But still, before I ditch it altogether, I'll pull the MAF sensor out and check for oil. If it passes this test, I'll try to improve the CAI (check for leaks) and give it a second chance.
I'll be updating my progress when I can make some time for it. Probably later along the week and on the weekend.

Have a great week folks!

I agree that it is almost certainly the CAI, but using the same sensor in its current condition in the original intake would be very strong evidence and may keep you from chasing the wrong problem.

I think your concept is good, but the MAF housing is just too big, mostly because of your fuel options. I can think of three possible solutions:

1. Find a slightly smaller MAF housing - Smaller than stock may even help reduce the effect of the fuel's ethanol content
2. Modify the housing you have to reduce its diameter - Carefully to avoid anything that could come loose
3. Wire a signal conditioner into the MAF output to the ECM - Also carefully to avoid damage

 

[Soulvivor]

Older post but how did this work out for you @agent008? I know this doesn't really do anything performance wise but I do like the sound they create. Similar to the ol 4 Barrel😁
I do not want to create anymore CEL's 😏

 

[agent008]

Older post but how did this work out for you @agent008? I know this doesn't really do anything performance wise but I do like the sound they create. Similar to the ol 4 Barrel😁
I do not want to create anymore CEL's 😏

Yes it did. I kept getting a "System too lean" code (P0100 I think) until I found a part of my hodgepodge intake that wasn't very well sealed. I rectified that and ever since drove around 1.5k miles and only got the code once. I used to get the code every now and then even before installing the intake -- I believe it is due to poor fuel octane here in Brazil. So one might say it worked out well, yes.

EDIT: P0100 is what I'm currently having on my diesel Fiat Toro truck (different issue, MAF reading drift beyond range, signal too low). The Solstice code was always P0171 (System too lean).

 

[agent008]

No codes before.

To be accurate, I did state I had no codes before but I did have a very occasional P0100 P0171 code before. So after I solved my intake leak I got back to the same status as the OEM intake, but with a better sound and no need to import a panel filter every 6.000 miles.

EDIT: code was P0171.

 

[Soulvivor]

To be accurate, I did state I had no codes before but I did have a very occasional P0100 P0171 code before. So after I solved my intake leak I got back to the same status as the OEM intake, but with a better sound and no need to import a panel filter every 6.000 miles.

EDIT: code was P0171.

Thanks for the update!