2007 Yukon Denali crank no start after driving

[alpha_omega]

Talked to the shop. They did not relearn and had no clue what I was talking about….

Hopefully they knew what they were doing when installing it. I’m guessing they didn’t tell you if they checked either of them to ensure they were/weren’t working before hand?

How new is the battery? Have you had it checked? Something a simple as a bad ground or weak connection could become worse from a bad motor Mount or blow shock/air compressor. Then when the vehicle slows down and things shift (the nose dives forward during braking, or you make a turn into a parking lot and the right side/left side angle increases/decreases) your connection could move enough to throw things off.
I’m not saying this is the case, but before you go throwing anymore money into it, I’d say start with the simple things first.

 

[Dan Sho]

Thanks yes I doubt they verified it was toast and I’m guessing it was fine but who knows. The battery is a year old. I agree with the ground issue however it not wanting to start for 15-20 min is odd and since it’s so freaking cold here if I pop the hood it will start even sooner. If I keep it running and shut it of it will restart. If I let it die it’s a waiting game.

 

[Fless]

Talked to the shop. They did not relearn and had no clue what I was talking about….

Need to get that done, if not for peace of mind. Any time a crank sensor is replaced, a relearn should be done. To skip that step invites misfires in the future.

Wes does one here, start at about 11:10:

 

[Dan Sho]

Need to get that done, if not for peace of mind. Any time a crank sensor is replaced, a relearn should be done. To skip that step invites misfires in the future.

Wes does one here, start at about 11:10:

Sweet thanks yes I agree. Can’t with my scan tool probably have to take it in to do it. Won’t be to the garage that replaced it though.

 

[alpha_omega]

That’s all helpful info. Remember the more info you can give us and the better picture you’re able to paint, then the better equipped we are when trying to help you get to the bottom of your issue(s).
Your service stabilitrak light sounds like either the TSB link I sent you or the brake pedal sensor. Start with the TSB and checking your grounds.

Grounds:
*Drivers Side (a.k.a. Left or LH)
*Passengers Side (a.k.a. Right or RH)
Rear Left - Inside Bumper mount (go just behind the fuel cap, look under the rear panel and then back toward the bumper. You’ll see two grounds.

Mid Left - Under the drivers door on the frame mount.

Front Left - Check your fuse box to ensure all of your fuses are good. Check the connection at the alternator and the ground strap at the back of the engine.
There are others on the engine block as well as several other locations throughout the vehicle, but the ones subject to movement, rust and corrosion are the main concern. I can send you a list if needed for the others, but let’s not get too ahead of ourselves.

Front Left & Right - Lower left and right of the radiator core support.

You mentioned pressure earlier. Are you seeing a drop in your oil pressure or just your fuel pressure?

What’s the mileage on this vehicle and what maintenance has been done that you are aware of?

 

[alpha_omega]

Have you taken the battery in to have it tested?

Did everything check out with the fuel system?
That 15-20min lag almost sounds like a fuel pump issue, but im not sure if that would be a concern with it being an ‘07. Someone else can chime in on this one.

 

[Doubeleive]

I’ll add again also that I dumped a quart of the trans conditioner in like in other threads wilts no change. Hooked up a fuel pressure gauge to see what happens when it dies we’ll see what I get. As of now it’s running 60 at idle. Might try the lower viscosity engine oil trick but being it’s subzero to low teen temps here the last month I have my doubts with that fix. I’m due soon anyway though. Also plan on grabbing a fuel pump relay and monitoring the oil pressure when the problem occurs.

60 is high, should be around 44-50 with engine running, not sure if 60 would affect anything but from what I gather that seems high, pre-start pressure should be 60-65
what does the fuel pressure do when it starts to die? is it dropping or staying static?

 

[Dan Sho]

That’s all helpful info. Remember the more info you can give us and the better picture you’re able to paint, then the better equipped we are when trying to help you get to the bottom of your issue(s).
Your service stabilitrak light sounds like either the TSB link I sent you or the brake pedal sensor. Start with the TSB and checking your grounds.

Grounds:
*Drivers Side (a.k.a. Left or LH)
*Passengers Side (a.k.a. Right or RH)
Rear Left - Inside Bumper mount (go just behind the fuel cap, look under the rear panel and then back toward the bumper. You’ll see two grounds.

Mid Left - Under the drivers door on the frame mount.

Front Left - Check your fuse box to ensure all of your fuses are good. Check the connection at the alternator and the ground strap at the back of the engine.
There are others on the engine block as well as several other locations throughout the vehicle, but the ones subject to movement, rust and corrosion are the main concern. I can send you a list if needed for the others, but let’s not get too ahead of ourselves.

Front Left & Right - Lower left and right of the radiator core support.

You mentioned pressure earlier. Are you seeing a drop in your oil pressure or just your fuel pressure?

What’s the mileage on this vehicle and what maintenance has been done that you are aware of?

Weather is hopefully gonna break in couple days I’ll check the grounds. 154,000 I’ve owned it for 2 years and in that time Other than fluids I’ve done spark plugs, wires, starter, under hood fuse block with all new fuses (due to no crank no start a year ago) battery, tps , cleaned throttle body, crank sensor, and I think that’s about it. Not seeing any fuel pressure drop just want to monitor it to be sure. Oil pressure does go lower when warm or at stop like 15-20 when at 600 rpm but planning on a better log of that this week. This vehicle was purchased from a previous mechanic who seemed very knowledgeable for whatever that’s worth. Service suspension has been on since I have owned it and airbag light turned on 3k ago still waiting on recall parts for that.

 

[Dan Sho]

60 is high, should be around 44-50 with engine running, not sure if 60 would affect anything but from what I gather that seems high, pre-start pressure should be 60-65
what does the fuel pressure do when it starts to die? is it dropping or staying static?

Thats why I hooked the gauge on. I’ll find out tomorrow what it’s doing cause I’m not sure. The garage said it was good but I'm past trusting them. I work on the road in sales so I’ll have plenty of time this week sitting and checking after it dies.

 

[alpha_omega]

Again…all good info for us to know. Thank you for that.

Have you checked the connections at the fuse block to make sure nothing has come loose since the install? Same goes for the wiring harnesses and pos/neg cables.