No start when hot 2007 Pontiac G6 3.5L

Boomer

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Hey boomer, long time no speak.

I found this TSB which seems to apply.

I also included whole wiring for the car. notice where the ground G302 is. Try cleaning that first. It says under left rear seat back. Page 2 of four.
Yes, great to see you, Nick. You are the best, buddy. These diagrams will help alot. Reading the TSB which also helps quite a bit. It seems to be just like what I found while googling. It seems to say to replace the terminal itself with Part number 13575721 ASM wire splice.
Other G6 owners have had the hot start problem and said replacing the underhood fuse box fixed it. I think it's discontinued though. I did see a pic of a mod a guy did. I'll include the pic. I did spray some gumout in the throttle body area to at least clean the area around the butterfly. (Do they still call it that?) Anyway I digress.

I also watched a youtube video of a G6 vehicle where they found a bad ground. It was the guy that goes by ScannerDanner. So I certainly hear you on the grounds. I don't expect you to watch the whole thing. I'm just going to drop the link for future use by myself or anyone interested.
 

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Boomer

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If you can get your hands on a power probe four, I f ing love this thing.

Great investment if you work on cars regularly.

It has a resistance option with live feed. Absolutely great just for things such as this.

Also, as grc noted, wiggle testing is good, but if that is no go, look for restrictive grounds. Or choke points as we say in the industry.

Here is a short video of what a power probe 4 is and how this cheap thing can be of value. And NO, I dont endorse this company, I just like the tool cuz it actually does what it says it does and is very robust. Worth every penny I spent in my mind.

I have seen several videos in the past with the power probe and have thought about it. I don't think it was the 4. I think I've seen the 1 and 2. It certainly does look like a great tool. I'm guessing each version gets better? I'm tempted. I don't work on them often like you do but, I like tools. :D My Voltmeter can't do quite the things this can do.
 

Boomer

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So if you took the time to make it to the end of alberta guy video, the feed test option is what I love the most for problems such as your (I think daughter ride)

I catch alot of problems my regular multi meter wont cath, cuz this one actually gives me a reading on voltage drop in a circuit and I can also read ohms at same time. This it where it shines.

That is how I found that buick problem, which had exact same symptoms and problems as this g6. In my opinion, g6 and buick of same era, those PDC's sucked large, much like mopar ones.

Anyway, nuff talk, try ebay or similar for the probe 4. The hook is out now, but WAY to costly to justify an investment yet as I have all kinds of other shyte to work with, but man, do I love my probe 4 for things such as this thread.
I watched it a couple of times. I enjoy the electrical stuff. Well except when you can't get to the damn wiring. :p

Here's a quick question unrelated to the issues mentioned. There's a tee underneath the coolant reservoir on this car. I've replaced one hose that I thought was leaking and it seems to have slowed down but, there's still a leak. In your experience (this goes for all of you mechanics here) does this plastic tee leak very often or, is it usually a hose?

Thanks so much for your help.
 

nickb2

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this plastic tee leak very often or, is it usually a hose?
More often than not, it is the plastic tee or the reservoir itself, different materials leak over time, the hose most will not if spring clamp still good.


I have replaced several of these just in the past year, they all crack at same place.

I will include a link, ask any tech, these gm jobs with vintage saturn stuff from the olds days. Cracks right where you see the molding seam at bottom.

 

Boomer

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More often than not, it is the plastic tee or the reservoir itself, different materials leak over time, the hose most will not if spring clamp still good.


I have replaced several of these just in the past year, they all crack at same place.

I will include a link, ask any tech, these gm jobs with vintage saturn stuff from the olds days. Cracks right where you see the molding seam at bottom.

Ok, thanks Nick. I would think the reservoir would be something I could see leaking. It seems to be leaking at the tee. I've replaced one hose and it seems it may have slowed but, still has a leak. I'll have to figure out new part number and replace it. It can't be that expensive.
 

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.
I wanted to update this. I had been working a bunch of 12 hour days. In my last post, I said I had to work 12 hours the next two days. I talked to her the 2nd day and told her I could work on it the next day. She said it's at the local shop in town. She didn't want to wait and her mom said she would pay for it. Turns out we were on the right path. @grcauto was on the money with the wiring. It did turn out to be the ground we wiggled once and it made the car die.
I am going to include a pic of the shop receipt so that you guys see exactly what they said. In there apparently she told them we fixed that ground but, that was not the case. I didn't have the right connector on hand to do it so it hasn't been repaired. Hopefully no other issues crop up from it but, if they do, I have the stuff on hand to do a proper repair now. I did not see exposed wiring at the MAF but, we did concentrate on the ground area most because there were so many issues. I've even posted a 2nd thread which I may duplicate this post there. She hasn't mentioned any issues returning as of yet so we will see.

I have to thank all of you guys for the help. billr, grcauto (you had it right) nickb2 you always give great help and providing diagrams well, it doesn't get much better than that. I see the ground for the MAF sensor came from G106 (which is the ground we wiggled and planned on fixing)

Here's what the mechanic did specifically.
 

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grcauto

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I'm glad they were able to fix it correctly. The wiring on these low voltage systems are very picky and must be solid at all connections.
 

Boomer

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I'm glad they were able to fix it correctly. The wiring on these low voltage systems are very picky and must be solid at all connections.
Thanks. With your help, I'd have gotten it. I'm ok with this though. I have plenty of things to do.
 
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