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Discussion Starter #1
I'm getting a CEL still, running too rich.

As far as I know, this is opposite of what the MAFci is taking care of. I have soldered the connections in and I had the box replaced by CPE.

I also cleaned the MAF and IAT with some electronics cleaner and the IAT appears amber now.

I just used some fuel injector cleaner to make sure that they aren't dirty or something.

Is there anything else I could be missing? Are the spark plugs perhaps not gapped correctly? I'm at my wits end on what to do next.

My idle is at 750-775RPM which I think is high because my gf's 2.3L 6 has idle lower than that around 600.
 

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Best bet would be to find a shop with an A/F meter to check it out to be sure it is actually occuring. Ca you feel the car noticeably bogging down?
 

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Discussion Starter #6
I've reset them using my autoenginuity tool. If it happens again, I'll get the freeze frame and post up the A/F ratio if it has it.

I could go do a live reading now and see what its at, what should it be at when idling?
 

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I just cleaned up the wires under the hood and when I turned the car I was getting a CEL. After trying everything the simplest thing I tried was the thing that worked. Just disconnect the battery, let the power drain out of the system(I pumped the brakes), then reconnect, let power up, start car.
 

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Discussion Starter #9
Well that won't get rid of the problem if its mechanical.

Anyway, I did a little more investigation with my scan tool and here's what I found and what I think may be happening, feel free to offer your opinions or help.

I saved a data log of a couple things and I averaged the values out over time and these are the values I got:

Short Term Fuel Ratio Bank 1 = -.58%
Short Term Fuel Ratio Bank 2 = -1.04%
Long Term Fuel Ratio Bank 1 = -24.7%
Long Term Fuel Ratio Bank 2 = -24.84%

B1S1 O2 Fuel trim = -1.08
B1S1 O2 Voltage = .4615
B1S2 O2 Fuel trim = 99.06
B1S2 O2 Voltage = .000256

B2S1 O2 Fuel trim = -1.18
B2S1 O2 Voltage = .51256
B2S2 O2 Fuel trim = 99.06
B2S2 O2 Voltage = .00089

My thoughts:

Both STFT and LTFT in bank one and two are negative indicating a lean condition. Could my MAFci be over compensating for a lean condition and causing the LTFT to be negative?

My B1S2 and B2S2 O2 Fuel trims are way high at 99.06 and voltages are also low, not sure what might be causing this.

Could I also have leaking injectors? Sometimes when I cold start, I can smell a little gas which could be some kind of leak into the cylinder. How would I check this?

Basically from what I've read, LTFT and STFT should be as close to 0 as possible. Since they're on both banks (1 and 2) then there's something other than bad injectors. Could it be the fuel pump delivering too much fuel? Or even a communication error where the computer can't update the STFT and LTFT calculations quick enough.

I usually get the CELs after spirited driving, highway driving and always coming to a stop or idling. I hope its not the communication error, another thing that leads me to believe it could be is that it takes a while to read DTC codes using the autoenginuity tool, sometimes 5 to 10 minutes to get a code.
 

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That really really sounds like the wrong wire has been tapped into (to me anyways, but I don't know much). If you don't get it figured out this week, I'm sure there will be a bunch of help at the Mid-Ohio meet to get it fixed.

I know you've checked and checked, but thats just what it sounds like to me even though its probably not it.
 

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Discussion Starter #11
I'm tapped into the wires that were in the installation guide, so if that's wrong, then that's my problem.

From what I've been reading it may be a bad MAF. Does anyone know how to do the BARO PID test? Supposedly its an indication if the MAF is bad.
 

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Wow those numbers are WAY off. I'll try to cap my mafci later today (or tommorow), but they should be around -4 to -7 variance for the SFT's (depending on front/rear bank), and no where near that high for the LFT's.

It almost seems like a completely reversed mafci box...its like its running the fuel curve backwards. Have you tried bypassing the mafci and checking your SFT/LFT's? Did you recently get a PCM reflash?

(Remember a negative number indicates the PCM is removing fuel (ie too rich) The injen intakes tend to see LFT's in the 20% or higher range (adding fuel)).
 

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Discussion Starter #13
I was getting rich codes with an old box and had it replaced by CPE, I get them but not near as often.

Should I leave the intake in and bypass the MAFci or return to stock and bypass it? I hate taking that stuff out of there :p

I have the latest PCM version. Also on friday, I plan to swtich out my MAF with mike2005's when I meet up with him. I'll take some readings then just to see. Maybe I"ll change out the box with his too if I can get it off easily.
 

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If it were to do with the latest flash, don't you think more people would be experiencing it?
 

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Discussion Starter #17
I didn't get the fuel trims read yet with the bypass on. I'm just posting because when I started it up after class, it hesitated. Then when I put it in reverse, the idle dropped to about 500RPM. I shut it off and tried again and it hesitated, put it in reverse and the idle dropped.

I drove it home and did it again at home and it started up just fine. I hope its not the TPS again.
 

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I didn't get the fuel trims read yet with the bypass on. I'm just posting because when I started it up after class, it hesitated. Then when I put it in reverse, the idle dropped to about 500RPM. I shut it off and tried again and it hesitated, put it in reverse and the idle dropped.

I drove it home and did it again at home and it started up just fine. I hope its not the TPS again.
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Call George tomorrow and have him ask Shawn or one of the other techs, I am sure they will help you out!
 

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Discussion Starter #19
I just didn't want them to have to work on the car that weekend if it'd take a while to check stuff out on it.

Ok, I just took some readings before I disabled the MAFci and after I disabled it. Unfortunately, I didn't get a good log. However, before I took it off, the LTFT and STFT were both negative as before as well as the S2 O2 fuel trims were still high.

I bypassed the mafci box and read it again, the STFT was 0 while the LTFT was still negative about the same as before. The S2 O2 fuel trims were also the same. The engine idled roughly as expected.

I measured the barometric pressure which in the car states 28.91in, weather.com has it listed currently at 29.73in. If these were way different, then that would lead me to believe the MAF itself is bad, since they aren't dramatically different, I don't think its the MAF. Therefore, either the box is bad and I just didn't give it enough time to adjust, or I have some kind of fuel delivery problem.

Comments?
 

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Mad,



Here's my data at idle to compare. This is in closed loop. A second early each % was 2% less. This is right after my commute home, after pulling in the driveway. (First I turned off the car, then I remembered that I was supposed to snag some data for you, so started it back up again)

In open loop (not captured), my readings went to 0.7% for the front back, and 2.4% for the rear bank. (LFT's)
 
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