Engine Codes

Briann1177

Goblin Guru
On a side note, I started to question my MAP sensor for some reason. Come to find out, it's spot on with the pressure gauge I have hooked up. I'm confident that all my sensors are working correctly. I think once I get my leaks sealed up, I'll be good. Hopefully.
 

ctuinstra

Goblin Guru
Are those silicone heses and the pipe sizes different? They almost have to be in order to leak that much. If they were made for each other, I would think they would be a good fit and the clamps just seal them up. Sounds and looks almost like the hoses are bigger than the pipe and you are having to crush the hoses.

Sounds like you are really onto something! I was trying to tell you something's wrong.
 

George

Goblin Guru
You can hook your smoke machine to the turbo inlet when all done to test the complete system. In our shop our smoke macHine is used every day after having an intake apart. We remove the air mass meter and tset every thing. I would no run that crankcase vent to the pressurized side of the intake.

Brad
 

Briann1177

Goblin Guru
The boots appear to be the correct sizes. After I hooked all the plumbing back up and paying very close attention to how things fit, I went for another test drive. Unfortunately the P0101 code came back right on cue. I came home, cleared the codes, and went for another drive. This time the code did not come back. I'm not sure if the warm restart had anything to do with it not coming back so we'll have to see.

I'll try again tomorrow. If I'm still having issues, I'm going to take the smoke machine advice.

I really appreciate the input.
 

Nilbog

Well-Known Member
Do you have a spare ECM you can swap in? I've seen corrupted units in the past (on other vehicles) that wouldnt right themselves.
 

Briann1177

Goblin Guru
I don't have a spare ECM. On a side note, the P0101 code is still coming back after fixing leaks that may or may not have been there in the first place. I've officially given up. I found an ASE Blue Seal shop, and took it to them. Not sure what Blue Seal really means as far as quality. It's probably just a cert to jack up their prices as a marketing gimmik. Anyways, they said they can do pressure/smoke tests, so I'll have to wait and see.
 

Briann1177

Goblin Guru
Got the car back from the mechanic. They didn't see anything wrong. They're blaming it on the cold air intake. I took it for a drive and did some data logging in Torque. First thing immediately obvious is my long term fuel trims started off at -15 at idle. Throughout the drive and within a couple minutes, they got more and more negative and capped out at -25 through the rest of the trip. No fluctuation at all once they maxed out at -25. STFT seem to be more normal around -5 to +10 or so. Even with the PCM pulling that much fuel, I'm still getting a P2178 (Too rich on idle and accel) and the car reeks of a very rich exhaust. I don't think there's any way I'm leaking that much air for for it to do that.

One thing I noticed in torque is that I'm not getting any readings for my O2 sensor. I'm not sure why. Can somebody confirm if they see something similar to these screenshots? These are the only O2 sensor related numbers I get.

Screenshot_20180827-163426.png
Screenshot_20180827-163437.png
 

Waterdriver

Goblin Guru
Form the Torque display. It looks like you might have the downstream O2 wiring connected to your sensor.
Located the other O2 wiring plug and try connecting to the O2 sensor. (Upstream O2 plug)
Looks like the ecm doesn't see any O2 readings from the upstream O2 sensor and is going to the default full rich mode to protect the engine.
 

Lonny

Administrator
Staff member
You have the same cold air intake as Matt (off the ranch), Jim L (4j) and Kevin D.
I know Kevin has a stock turbo with a stock tune and Matt has a big turbo with a big tune.
Did you reuse the same ECM, MAP sensor, TMAP sensor and injectors that came with your donor?
 

Adam

Administrator
Staff member
One thing I noticed in torque is that I'm not getting any readings for my O2 sensor. I'm not sure why. Can somebody confirm if they see something similar to these screenshots? These are the only O2 sensor related numbers I get.
The only LNF we have in our possession is a Solstice GXP. I logged it a couple of weeks ago with HP Tuners and noticed that the O2 Voltage B1S1 always shows 0.000 V.
 

Briann1177

Goblin Guru
You have the same cold air intake as Matt (off the ranch), Jim L (4j) and Kevin D.
I know Kevin has a stock turbo with a stock tune and Matt has a big turbo with a big tune.
Did you reuse the same ECM, MAP sensor, TMAP sensor and injectors that came with your donor?
Yes, everything is stock. ECM, MAP, TMAP, and injectors. MAF is new only because I thought a new one would fix it. The fuel tank is also vented.

I don't understand why torque isn't displaying the O2 sensor readings. I'm not sure if my current O2 sensor is acting up (no related codes unless I unplug it) or if there is something goofy inside Torque and the way it reads data from a Cobalt. I would think that the voltages should vary between 0V and 1V with .45 being the nominal value. Hoping someone can confirm that with their Torque.
 

Brian74

Goblin Guru
That ECM is sensing rich and telling the fuel trim to lean things way out, which it is. You say its still running rich. Possibility of fuel injector stuck open? Still, it seems now like a different issue than last time.
 

ctuinstra

Goblin Guru
What injectors do you have in there? I have almost the exact same issue with the 60lb injectors. I have/had a tune from ZZP on the donor. I even had the same Too Rich Code from time to time. My injector data has been modified to “match” the injectors but these ECMs are maxed out at 63lbs. I was able to change the injector voltage factor to remove more fuel and so far no code. I still need a full tune but can’t really do a good tune with the new MPVI2 since they haven’t released the analog/digital input adapter yet. I also noticed I have a very high fuel pressure which is causing an over-rich condition.

Have you put a fuel pressure gauge on it yet?

I’m known I can only monitor one O2 sensor since I only have the one and it’s not a wide-band. I do have a wide band gauge that I will be hooking up as soon as the weather gets a bit better.

1) are you sure they are stock injectors? Not trying to be an ass, but could the PO have changed them? I looked up the number on the side of mine to find out they were 60lb.
2) what is your fuel pressure?
3) do you know for sure there is no tune on the ECM?

Sorry if you have answered some of this, I’m on my phone and it’s a pain to search through the thread
 

Briann1177

Goblin Guru
Great questions that I wish I had answers to. I don't have a fuel pressure gauge to check that. I might need to invest in one.

As far as the PO, I really have no idea what has been done. I'm going way out on a limb here and assume it's bone stock. I only say that because of the Carfax report. The PO was a stickler for maintenance and he used the dealership for things like oil changes. The interior was also well kept. Maybe he did that for warranty reasons or maybe he was a guy that doesn't like to mess with things. To me that says the PO was a guy that valued the car, and probably didn't want to beat on it like a typical Cobalt owner. I really have no idea though.

I'm guessing there is really no quick and easy way to peek into an ECM and see if things are stock or not? I don't have access to an HP tuner. I would like to do a reflash, but I'm worried about it breaking things even more based on what the dealer was telling me.

I'm still in the process of eliminating mechanical problems like O2 sensors, fuel pressure, etc. I'll go the tune route if I can't figure out why my LTFTs are so out of whack.
 

ctuinstra

Goblin Guru
The fuel delivery rate of the injectors are very dependent on the fuel pressure. I know I am running really high pressure caused by the fuel filter/regulator on my car which is not the exact same filter that was on the donor. I would invest in a pressure gauge to check it off the list. I believe it should be around 58lbs. Mine is running around 80! I can guarantee it is delivering much more fuel per pulse at 80lbs than is would be at 58lbs.
 

ctuinstra

Goblin Guru
Also, you can view the calibration on any ECM without worry of changing anything. It they are telling you anything different, I don’t know if I could trust them if they have problems doing just that.
 

Nilbog

Well-Known Member
That ECM is sensing rich and telling the fuel trim to lean things way out, which it is. You say its still running rich. Possibility of fuel injector stuck open? Still, it seems now like a different issue than last time.
Can you move the injector to another port and see if it tracks?
 

SliderR1

Well-Known Member
Has your O2 sensor been verified to be in working order? I would figure out a way to test it and validate that isn't the problem.
 
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