2013 Caprice 1100 RPM idle

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Revdoc
Posts: 5
Joined: Fri Mar 29, 2019 6:24 pm

2013 Caprice 1100 RPM idle

Post by Revdoc » Mon Aug 10, 2020 9:22 pm

I have a '13 PPV that has an occasional high idle problem, it sometimes wants to idle at 1100 RPM. It always seems to happen when the car is warm or hot, never on a cold start. I can sometimes get it to go back to a normal idle of 650-700 RPM by turning the car off and restarting it. It was happening today so I tried to narrow it down, what seemed to work was turning off the car, opening the door and waiting about 30 seconds before restarting. This makes me think it is not a mechanical problem, but something in the tune. I'm guessing there is a set of parameters that make the PCM will command a high idle and one of them is the engine run time, turning off the car and opening the door "resets" one of the parameters and fixes the idle.

There are no codes or check engine lights. I can see the commanded idle in HP Tuners is set to 1096 RPM or very similar, close to 1100 but not exactly. This also makes me think it is not a mechanical problem but an electronic one. I have found aftermarket idle controllers for emergency vehicles but since the PCM is commanding the idle at 1100 I am assuming it isn't an aftermarket device. Has anyone else run into this? I've searched and not found much.

Phxcaprice2012
Posts: 5
Joined: Wed Jul 15, 2020 11:42 am
Location: Glendale AZ

Re: 2013 Caprice 1100 RPM idle

Post by Phxcaprice2012 » Tue Aug 11, 2020 11:06 am

I have had one instance recently where my 2012 did this, was in a drive thru line and it was about 118 out. I assumed this was a function of the system. When I shifted from park to drive it went back to normal idle. I did go back to park and idle was normal.118 degree temperatures can bring the gremlins out in vehicles. I did a pretty thorough search of the forum and was unable to find anyone experiencing the same. Hopefully someone can weigh in on this?
-Brett
2012 Caprice 9C1
2001 Tahoe 4X4

thirdgenfarmer
Posts: 64
Joined: Sat Apr 29, 2017 4:47 pm

Re: 2013 Caprice 1100 RPM idle

Post by thirdgenfarmer » Tue Aug 11, 2020 2:22 pm

Phxcaprice2012 wrote:
Tue Aug 11, 2020 11:06 am
I have had one instance recently where my 2012 did this, was in a drive thru line and it was about 118 out. I assumed this was a function of the system. When I shifted from park to drive it went back to normal idle. I did go back to park and idle was normal.118 degree temperatures can bring the gremlins out in vehicles. I did a pretty thorough search of the forum and was unable to find anyone experiencing the same. Hopefully someone can weigh in on this?
I have had this exact thing happen - wasn't quite 118, but was sitting in drive through when it occurred. I put the car in park (or maybe took the car from park to drive) and the RPMs dropped to the normal range. Hasn't happened again and I attribute it to the temperature and sitting in a chain of cars where no cool air is coming into the car.
2011 9c1

"It's got a cop motor, a 364-cubic-inch plant. It's got cop tires, cop suspension, cop shocks..."

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