High Rpms in Park

[Kylejbriggs]

Currently out of town, but the wife is having problems with our 21 Yukon Diesel. She drove it today to work with no issues. When she went to start it, while in park it was sitting at 1000 RPMs with the check engine light on. She drove it and it started to overheat. I won’t be able to pull the code until I get home tomorrow.

Any ideas of what may cause this?

 

[DuraYuk]

Hard to say but generally idle will remain high initially to warm up. Could be thermostat issue or engine coolant temp issue.

Report back on what you find. A specific code would help.

You have warranty use it.

 

[BrokerThis]

Have her hit the onstar button to run a diagnosis on the CEL.

Depending on your location/climate, during winter 1000 is normal for me in the Michigan cold

 

[Stbentoak]

Have her hit the onstar button to run a diagnosis on the CEL.

Depending on your location/climate, during winter 1000 is normal for me in the Michigan cold

FYI unless you are subscribed to the highest tier plan, OnStar will not give you vehicle code information. As me how I know...
That's OK, I can pay for a code reader pretty quickly at the level I'm at...

 

[BrokerThis]

I didn't have an onstar plan when i used it before. they pulled the codes and emailed it to me last year with a CEL/transmission issue ....

 

[steiny93]

Currently out of town, but the wife is having problems with our 21 Yukon Diesel. She drove it today to work with no issues. When she went to start it, while in park it was sitting at 1000 RPMs with the check engine light on. She drove it and it started to overheat. I won’t be able to pull the code until I get home tomorrow.

Any ideas of what may cause this?

What do you mean by 'started to overheat'?
What temp did it get to? Did it push coolant? Does hvac heat work?

A wild guess... it's low on coolant and behaving poorly.
I believe the '21s have 5/100k powertrain on the diesels.

 

[Kylejbriggs]

From what she said was that it started to overheat. I just checked it and I don’t hear the fan that she heard. Check engine light still on with a P1006 code.

 

[DuraYuk]

From what she said was that it started to overheat. I just checked it and I don’t hear the fan that she heard. Check engine light still on with a P1006 code.

Has this yukon been refreshed/updated ecm? Longer crank times? I think this code is the one that was due to a misplaced reluctor/missing reluctor. The cure was to reflash. I don't remember seeing any overheating tho.

 

[Kylejbriggs]

 

[Kylejbriggs]

it won’t let me post a video but there is a fan going at idle after the car sat all day at work. Temperature that day outside was 50-60 degrees. Check engine light was on. She started to drive it and immediately jumped the temperature gauge that high. It reached 260 and the vehicle went into a safety mode. I got home today and the engine code I was able to pull was the P1006. It went on a flatbed and when I got to the dealer, the check engine light was off.