No start when hot 2007 Pontiac G6 3.5L

Boomer

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Make
Pontiac
Model
G6
Year
2007
Miles
158000
Engine
3.5
2007 Pontiac G6 with the 3.5L engine

I will be seeing this car for the first time tomorrow. My daughter just moved back to the area. I know it cranks and doesn't start if it's hot. Let it cool for awhile and it starts. She's going to need it to get a job. I searched this problem on google and found a few posters saying they had it and it's the fuse box. One person even states it's the ground wire for the pump relay. Again, I haven't seen the car to listen for the pump while hot. I'm just trying to see if you guys have more ideas. I'd really like to help her. Here is the link to that if anyone is interested. https://www.cargurus.com/Cars/Discussion-t9396_ds941120

I will be reading the codes tomorrow as well. She says there is also a problem with the traction control light coming on and the car starts jerking. I'll update with more info but, if you know anything to check now, I'd sure appreciate it.

Edit: The car had 9 codes stored and they are as follows. C0561, C0161, P0201, P0202, P0203, P0204, P0205, P0206, P0300

We got the car to full operating temp and the no start condition did not appear. Other issues did appear. I think I should start a separate thread for them.
 
Last edited:

billr

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There really isn't anything you can check until you get the car. Once you have it in a "no crank" mode, use a voltmeter to check for power at the starter-solenoid input stud, and check that the small stud there is getting power; check for both while trying to crank. If the small stud has power, does the solenoid make a big "clunk" when it is energized? If it clunks, then check for power at the other big stud, the one with just a short cable or strap disappearing to inside the starter motor; again, while trying to crank and in "no crank" situation. It is best to ground the meter right to the starter casing itself. The nose of most starters is bare aluminum, a handy place.
 

grcauto

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That is a typical crank sensor problem. Could be otherwise but we are guessing here and that is the first thing I would do.
 

grcauto

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There really isn't anything you can check until you get the car. Once you have it in a "no crank" mode, use a voltmeter to check for power at the starter-solenoid input stud, and check that the small stud there is getting power; check for both while trying to crank. If the small stud has power, does the solenoid make a big "clunk" when it is energized? If it clunks, then check for power at the other big stud, the one with just a short cable or strap disappearing to inside the starter motor; again, while trying to crank and in "no crank" situation. It is best to ground the meter right to the starter casing itself. The nose of most starters is bare aluminum, a handy place.
He say's it's a crank no start.
 

billr

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Oops! That is going to be much tougher, but not necessarily expensive. The ELM327 type links are cheap, but more of a learning-curve than a standalone scanner. Generally, you only have to resort to parts-swapping if you are short on time and long on money.
 

grcauto

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Crank sensors and ICM's are common for hot soak no start problems.
 

Boomer

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Ok, The car had 9 codes stored. She said the check engine light was not on today. It has 158,000 miles. I have found a leaking antifreeze hose. I will fix that.

The codes are as follows. C0561, C0161, P0201, P0202, P0203, P0204, P0205, P0206, P0300
 

grcauto

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Ok, The car had 9 codes stored. She said the check engine light was not on today. It has 158,000 miles. I have found a leaking antifreeze hose. I will fix that.

The codes are as follows. C0561, C0161, P0201, P0202, P0203, P0204, P0205, P0206, P0300
Those are likely P0301, P0302 etc.
These are the misfires for each cylinder. How do you intend on testing or are we guessing?
The comm codes are not about the engine at all they are the ABS and trac control.
 

Boomer

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Those are likely P0301, P0302 etc.
These are the misfires for each cylinder. How do you intend on testing or are we guessing?
The comm codes are not about the engine at all they are the ABS and trac control.
I hear what you're saying. The scanner reported P0201-0206 and said "Engine Injector circuit open cylinder 1. Same for all 6 cylinders. It's an intermittent condition. The traction control disable light came on and the car would start running funky. We would clear the codes and it would come back. We restarted it and suddenly, it would run fine.

One weird thing that I noticed. It would be running ok and then you drop it in reverse and it would die sometimes right away or after sounding like it was going to die(like the idle had dropped too low or something). In Drive, it ran fine. When she left, it was running fine. The car did sit for about 8 months but, she drove it here for about a 2 hour trip and she said it was fine.

The scanner has a code lookup feature that has stored frequently reported fixes. Frequently reported fix for C0161 was, replaced brake pedal position sensor. She says she did that. (She had an old part with her) I guess she had OReilly or someone read it and it said that so she replaced the switch. Doesn't seem to have helped.

C0561 ABS System disabled. Information stored Invalid serial data received. Reported fixes 1. Replaced Brake pedal position sensor 1. Repaired BCM Connector. 2. Repaired O2 sensor Bank 1 Sensor 1 wiring. 3. Replaced 02 sensors.
 

grcauto

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I hear what you're saying. The scanner reported P0201-0206 and said "Engine Injector circuit open cylinder 1. Same for all 6 cylinders. It's an intermittent condition. The traction control disable light came on and the car would start running funky. We would clear the codes and it would come back. We restarted it and suddenly, it would run fine.

One weird thing that I noticed. It would be running ok and then you drop it in reverse and it would die sometimes right away or after sounding like it was going to die(like the idle had dropped too low or something). In Drive, it ran fine. When she left, it was running fine. The car did sit for about 8 months but, she drove it here for about a 2 hour trip and she said it was fine.

The scanner has a code lookup feature that has stored frequently reported fixes. Frequently reported fix for C0161 was, replaced brake pedal position sensor. She says she did that. (She had an old part with her) I guess she had OReilly or someone read it and it said that so she replaced the switch. Doesn't seem to have helped.

C0561 ABS System disabled. Information stored Invalid serial data received. Reported fixes 1. Replaced Brake pedal position sensor 1. Repaired BCM Connector. 2. Repaired O2 sensor Bank 1 Sensor 1 wiring. 3. Replaced 02 sensors.
Sounds like the wiring is being stressed. Look at the engine while someone puts it in R and D and watch it move. You could also just start wiggling the wiring while engine is running and see if you can find it. I think you will.
 

Boomer

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Sounds like the wiring is being stressed. Look at the engine while someone puts it in R and D and watch it move. You could also just start wiggling the wiring while engine is running and see if you can find it. I think you will.
Thank you very much. It's great to have a plan of attack. She will bring the car by again on Thursday as I work 12 hour shifts the next two days.
 
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