Cadillac Owners Forum banner

1 - 11 of 11 Posts

·
Registered
2018 ATS 3.6 Prem Lux
Joined
·
5 Posts
Discussion Starter #1
I've got a rough idle that comes up randomly. My ATS is a 3.6, and only has 10K on it. Today, I was driving and the check engine light came on and the message 'engine power reduced' but it was running fine and I didn't notice any change in engine power at all. I've had it to the dealer twice now to try to figure out the rough idle problem. Seems to happen after driving at least 20 minutes, and either in park or at a stop light in drive with the brake on.
Any ideas on what is happening here? I love driving this car, but I'm starting to worry if I got a lemon...
Thanks!
 

·
Registered
Joined
·
27 Posts
If the check engine light came on there should be a trouble code stored. Have the car scanned and post what code comes up.
 

·
Registered
2018 ATS Sedan Turbo AWD (stablemates 2019 Corvette Stingray + 2010 LaCrosse CXS)
Joined
·
112 Posts
What did the dealer do and say?
 

·
Registered
2018 ATS 3.6 Prem Lux
Joined
·
5 Posts
Discussion Starter #4
The first two times, couldn't replicate the rough idle and the CLE hadn't come on yet, so nothing. This time, the light came on and I will be bringing it back in Monday (3rd time). Il let you know what they find then. Have you seen this problem before?
 

·
Registered
2018 ATS Sedan Turbo AWD (stablemates 2019 Corvette Stingray + 2010 LaCrosse CXS)
Joined
·
112 Posts
Yes but I did not suggest in your case given how new and low km your car has - the symptoms are just like what my cars demonstrate when the throttle body is dirty. But in your case this is highly unlikely...
 

·
Registered
2018 ATS 3.6 Prem Lux
Joined
·
5 Posts
Discussion Starter #6
Turns out it was the oil pressure solenoid sensor that causes the CEL. The mechanic at the dealership said he's not sure if it is causing the rough idle... and doesn't think that's it. I guess we'll have to see how it runs after they replace the part...to be continued! Lol
 

·
Registered
2014 ATS 3.6 Premium RWD, 2016 Corvette Z06, 2018 GMC Sierra Denali 2500HD Diesel
Joined
·
2,768 Posts
If he is talking about the solenoid associated with the VVT system, then it could be the cause of the rough idle. Camshaft "phase" is varied in this VVT (variable valve timing) to optimize engine operation under various conditions and depending upon the failure mode it could definitely cause a loping idle much like an older performance engine.

Even some of the VVT equipped engines (like the hotter versions of the LT series small block V8) have an idle lope as normal because the range of VVT control is limited and the timing is biased so that idle is just acceptable in order to use its available range to maximize performance over the power band.

Rodger
 

·
Registered
2018 ATS 3.6 Prem Lux
Joined
·
5 Posts
Discussion Starter #9
It's fine. I'll wait to see how it's running after i get it fixed.
Thanks.
 

·
2016 ATS Premium 6-spd MT
Joined
·
14,021 Posts
If he is talking about the solenoid associated with the VVT system, then it could be the cause of the rough idle. Camshaft "phase" is varied in this VVT (variable valve timing) to optimize engine operation under various conditions and depending upon the failure mode it could definitely cause a loping idle much like an older performance engine.

Even some of the VVT equipped engines (like the hotter versions of the LT series small block V8) have an idle lope as normal because the range of VVT control is limited and the timing is biased so that idle is just acceptable in order to use its available range to maximize performance over the power band.

Rodger
Bingo! Good call.
 
1 - 11 of 11 Posts
Top