2004 GMC Yukon Stalling problems

[m16dernwarfare]

I am having a strange problem with my current vehicle. I have a 2004 GMC Yukon suv with 300,000 miles. This car has run perfectly for its entire lifetime with no major problems.

I took it to an oil change place the other day for an oil change, tire rotation, and inspection. The maintenance was performed in a timely manner and the full car inspection only recorded good results, other than some age related issues.

After the servicing, I drove the car about a mile back to my house. As I was going up the driveway, the car unexpectedly stalled. The engine was completely shut down, pressing the gas pedal did nothing. The steering on the vehicle was completely immobile, I could not force the steering wheel to change directions. There was a battery warning light on the dash, but other than that, no check engine light or error code from the computer. The radio stayed turned on.

After a couple of seconds, the car slid back onto the road as if it was in neutral gear. I turned the key off and on again to restart the engine. The starting was sluggish, but the engine did restart. As I drove the car back up the incline and into the final garage parking position, it stalled again with the same symptoms.

What could be the cause of this problem? I have done some research and other older model yukon owners have encountered a similar problem. However, since it is random, it is hard to have it diagnosed by the dealership . I drove the Yukon around in the snow and ice today for 30min with no problems, even after trying to recreate the same scenario.

The last thing I want is to be in a turn on the highway, and to lose engine and steering power.

what could be the problem?

 

[SparkyJJO]

The battery light coming on is normal when the engine stops running, as it is telling you it is running everything off battery instead of the alternator. If the engine was still running and you saw that light it would indicate an alternator problem for example.

Stiff steering is also normal when the engine stops since you don't have any power assist. The only way it would be completely immobile is if you turned the key to OFF which may lock the column (not all vehicles do, my 02 Trailblazer does not lock the column for example and I'm pretty sure my 07 Silverado does not either). That said, trying to manually turn the wheel without power assist on a larger vehicle is going to be really darn stiff!

I'm assuming when you restarted you had to put it in neutral or in park. It shouldn't be able to crank the starter when in gear.

When it stalled, did it cough or sputter at all or did it just act like it was turned off with the key?

It could be something simple like a crank sensor or even an O2 sensor. When the O2 sensor in my Trailblazer died the engine pretty much shut down with it, although the computer caught that the sensor flatlined and went into "safe mode" quick enough that it didn't totally stall out.

 

[tortillasoup]

check the oil level while parked on level ground.

 

[LTC8K6]

Is it the GM key switch problem?

 

[bradly1101]

How's the carbon buildup in the EGR system?

 

[m16dernwarfare]

Yes, I put it in park to restart the engine after the stall. When the engine died out there was no sputtering, it was as if I turned the key to off.

The oil level is normal on parked ground.

I thought it could be the key switch problem, my keys are heavy. However, that recall was for later models, such as the 2009-2010, so I'm not sure if my Yukon would be affected.

I'm not sure how to check the carbon buildup in the EGR system. I have minimal car experience, this is my first car that I've owned (20yr college student).

 

[SparkyJJO]

I know on the Trailblazer platform the ignitions switch itself (separate part from the actual keyhole part) is a relatively common failure point for weird electrical stuff. Mine has never gone bad but others have. Not sure if that same issue translated to the full size or not.

The issue with the ignition on later GMs was more because they rotated the switch too much so when on the keys could actually use leverage to turn it off. Not sure why they did that. All my GMs (through 07) have the key barely tipped forward in "run" so even if I had a heavy keychain it couldn't turn the ignition off.

 

[LTC8K6]

You should see if any codes are stored.

 

[master_shake_]

the only thing i can think off is the main ignition line that feeds all the emission controls.

its a large pink wire coming off your ignition.

if it drops out while driving it will cause a stall.

if you open it up you can clean the contacts on it.

it looks like a bunch of fingers that are pushed in and out with a cog system that is built off the gear that turns them.

check them i bet they are black.

pop off the gray cover on the back and white or black on the front and sand the fingers.

or replace it.

chances are from the arcing caused by turning the car on and off your getting black arc marks on the switches fingers.

if they don't make proper contact you get a low voltage or no voltage and the ecm shuts down as well as everything else that runs off it.

fuel pump, injectors, coils etc.