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Discussion Starter #1
Just bought an 07 SS/SC for dirt cheap. Rebuilt title, after fixing some wiring that was not properly fixed right, I'm now onto the largest part, getting to run right. I'm getting codes

P0069- MAP Barometric pressure correlation
P0172- Rich bank one, and its running and smelling rich
P0315- Crankshaft position unlearned

(Sometimes a random intake performance code)

I just bought the car like this hoping an easy fix. Mods from what I can see so far, header, 3" exhaust, cheap little cold air intake and new filter I just put on, lowered, stage 2 clutch, poly mounts.

The car is very hesitant taking off, at half+ throttle it starts stalling out and the rest you will see in the video.

So far I have cleaned all vacuum lines, checked for vac leaks, took off throttle body and sprayed it out, replaced both skip and bar (Map) sensors and am still getting the code. I'm at a loss right now. Only possible other thing I think it could be is the vacuum actuator that the bar sensor runs to.

I've checked all power to map sensors and the actuator. Getting proper amount to all of them.

There is a mystery cable here getting 12v to it that I looked and looked and cannot figure out what it goes to, laying out under the TB area.



Here's a quick video

07 Cobalt SS Issues - YouTube

Also one of the wires I repaired seems to belong to the crank sensor that was poorly repaired and wouldn't let the car start when loose. Repaired it and I guess now that I may just need a case relearn for that once the car is running right possibly? The car is almost in drivable at the moment like this because any power to it causes it to cut out like its cutting fuel.

Any help would be appreciated. It's a great little car I just need to get it running right. Haha. Thanks a bunch for any help. Give me some ideas!
 

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What are the wire colors on that connector. You should top up coolant.lol
That looks like the connector for the coolant level sensor.
 

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Discussion Starter #3
Rebuilt title but they didnt replace the air bag. It's been half assed. Lol. But the wire colors are green and a peachy color.

---------- Post added at 01:15 PM ---------- Previous post was at 01:07 PM ----------

Yeah it says low coolant but its full. I don't know if I'm missing something it goes to or what from the wreck.
 

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Did you check the intake for cracks, especialy where the hose connects, it tends to break in a frontal impact.

---------- Post added at 06:34 PM ---------- Previous post was at 06:31 PM ----------

Are the wires on that connector solid colors.
 

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Discussion Starter #5
Where which hose connects? I have sprayed most everything with carb cleaner but will spray down the entire intake and check. But I may break out the soap and water everything looks clean though. It was a light impact didnt make it past the radiator and didnt bend the hood or radiator support.
 

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If wires are solid pink and solid light green it seems it would be the backup switch on transmission. Is it close by? Could it reach there?
 

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Discussion Starter #7
If wires are solid pink and solid light green it seems it would be the backup switch on transmission. Is it close by? Could it reach there?
Reverse indicator lights? I'm sure I could check. I literally climbed on top of the motor and was looking for a plug on the transmission. I though it was a speed sensor because the speedometer only goes up to 20mph and holds. But it appears something is already plugged in on top of the differential. I do believe they are solid colors. Am I right that its an F35 Trans?
 

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Is it Catless without a tune? Would explain the P0172.

---------- Post added at 07:50 PM ---------- Previous post was at 07:47 PM ----------

DTC P0069
Circuit DescriptionThe barometric pressure (BARO) sensor measures the pressure of the atmosphere. This pressure is affected by altitude and weather conditions. A diaphragm within the BARO sensor is displaced by the pressure changes that occur from varying altitudes and weather conditions. The sensor translates this diaphragm action into the voltage signal input that is used by the powertrain control module (PCM) for diagnostics and emissions control.

The supercharger inlet pressure (SCIP) sensor measures both the atmospheric pressure and the vacuum that exists under different operating conditions in the supercharger intake plenum. The plenum volume between the throttle body (TB) and the supercharger is where this sensor is located, and for the purpose of this diagnostic, this area is considered to be the intake manifold. The diaphragm within the SCIP sensor functions in the same manner as the BARO sensor. The sensors are not interchangeable. The actual measurement from the SCIP sensor is used by the PCM to calculate the difference continuously between BARO and SCIP. The calculated difference is displayed as the SC Inlet Pressure parameter.

The purpose of this diagnostic is to analyze the correlation between the BARO sensor, and the SCIP sensor. This is accomplished by comparing the difference between BARO and SCIP at key ON, engine OFF (KOEO), at closed throttle idle conditions, and at wide open throttle update events. At KOEO the difference between BARO and SCIP is represented on the scan tool by the SC Inlet Pressure parameter as a value that should be very close to zero. A negative SC Inlet Pressure parameter means that the BARO sensor value is less than the SCIP value. A positive SC Inlet Pressure parameter represents a BARO sensor value that is more than the SCIP value.

At idle the SC Inlet Pressure parameter represents the calculated difference between BARO and the reduced pressure that is present in the supercharger intake plenum as a positive value. At wide open throttle the SC Inlet Pressure parameter represents the calculated difference between BARO and the increased pressure that is present in the supercharger intake plenum, and should be very close to zero.

Both sensors have the following types of circuits:

• A PCM supplied and regulated 5-volt reference circuit

• A PCM supplied ground for the low reference circuit

• A sensor signal circuit that supplies a voltage input to the PCM

Changes in BARO due to weather are relatively small, while changes due to altitude are significant. Pressure can range from 56 kPa at an altitude of 4267 meters (14,000 feet), to 104 kPa at or below sea level.

If the PCM detects that the BARO sensor signal and the SCIP sensor signal are not within a calibrated range of each other, whether that value is negative or positive, DTC P0069 sets.
 

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Discussion Starter #9
I doubt it has been tuned. Everything seems done right on the car but don't believe it's been tuned. I figured it was running rich due to map codes. I'm just clueless after replacing both map sensors and the vac hoses are good. Getting proper volts to map sensors. Yet if I unplug both sensors, nothing changed just throws a low voltage code
 

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DTC P0315
Circuit Description
The Crankshaft Position (CKP) system variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the CKP sensor. The calculated error allows the powertrain control module (PCM) to accurately compensate for reference period variations. This enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load. The PCM stores the CKP system variation values after a learn procedure has been performed. If the actual crankshaft position variation is not within the CKP system variation compensating values stored in the PCM, DTC P0300 may set. If the PCM detects that the CKP system variation values are not stored in the PCM memory, DTC P0315 sets.

---------- Post added at 07:54 PM ---------- Previous post was at 07:52 PM ----------

Can you check if second HO2 has been disabled?

---------- Post added at 07:55 PM ---------- Previous post was at 07:54 PM ----------

Don't forget to look back because I edited some previous post with more details.
 

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Discussion Starter #11
How can I check? And so basically the crank sensor just need to be relearned because it has no parameters store to compare to from the sensor. I'm still thinking a possibility of the SC bypass actuator is faulty stuck or dirty site both sensors are new and the only connection between the two is that actuator and all plugs are receiving power.

---------- Post added at 03:04 PM ---------- Previous post was at 03:00 PM ----------

Typing from my phone. Sorry for the spelling. Haha. I appreciate the help. I SHALL get to the bottom of this. It's not a DD so I have all day to look and work on it.
 

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How can I check?
Check O2 readings front normally oscillates from .1 to .8 volts rear is normally stable at around .7-.8volts. If they both oscillate chance are your catless. If so you might need a wide band for the rear so short term fuel trim can work properly.
 

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Discussion Starter #13
Would that affect the map readings? But I will hook it up and check soon and get back to you. Pretty sure it's catless though.
 

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Would that affect the map readings?
No, map sensors are not affected by the fact your car would be catless. First map measures atmospheric barometric pressure and second one measures boost. You are getting a code because the measured value fall out of range of the preset value. If you change the pulley on blower for example you have to adjust these preset values.

Did you check your timing gears, because that engine sure sounds like it's off a tooth or 2 on one of the cams.
 

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Discussion Starter #15
Is there anyway to tell if you have a different pulley on it? If I can figure out how to get to the timing chain I will check. Car idles perfect when it's calmed down and warm. And when driving it runs smooth but will hiccup when you give it gas. And if you go half throttle or more it starts cutting out and stalling.
 

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Most aftermarket pulleys will be a billet color and say ZZP or something on it. Stock pulley is 3.4 in dia.
 

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Discussion Starter #17
Yeah this one looks factory and is black with blue headed bolts in it. I'm sure it's stock but will measure. You never know because the car has had a lot of work done that the PO didn't even know. When I get home I'm going to check timing some how. I looked and there is no cat on the car. I'm going to start it up and pull the vacuum lines and see if that changes anything. I think I found one that might be sucking a little air last night but it was late. And pull the actuator and see if I can clean it some how. And trouble shoot what all that loose wire could belong to.

---------- Post added at 06:38 AM ---------- Previous post was at 06:35 AM ----------

Also I'm looking for the stock intake tubing and box as well as the fuse box cover under the hood. If anyone has one let me know.
 

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Yeah measure that pulley because I believe the blue headed bolts means a stage 2 upgrade from stock.
 

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Discussion Starter #19
Wow. Would it be the same size as stated before for a stage 2? Any idea factory size? I replaced all vacuum lines and cleaned out everything today and started getting a vacuum sound. Checked, and the map code was gone. Took 10 minutes and a restart for it to come back. Drove it and it was driving a lot better even with the code still. But still could barely get it to hit 5 lbs of boost and was cutting out a lot less. May still be a vacuum issue but when the code was off it was just throwing 2 crank sensor codes still and was still acting like in the video. I drove it down the road a little bit ago and dropped it off to a good mechanic to look at tomorrow. He said we will figure it out. Could be a possibility of the SC gasket needing replaced, etc. so I cant measure the pulley right now. Would he need to know about the stage 2? And would it be linked to the way it's running? As if it somehow became un tuned from the wreck?
 

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Well maybe the guy never had it tuned, maybe he put the stage 2 in and decided to take for a ride before the tune and ended up rear ending somebody. That car really sounds like an untune upgraded car with a bad intake leak. lol I wrote all of that in one sentence. Did you notice what color the injectors were? Stock are lime green stage 2 are blue. Stage 2 pulley is 3.1 inch where stock is 3.4" according to BlackBalts.
 
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