So I had 1st rough cold start today

I'd chalk your experience up to the intake manifold problem. Unfortunately, you are beyond the powertrain warranty period, so the fix is not free.

It wouldn't hurt to check the oil control valve, though.

 

Had our 2011 intake manifold replaced yesterday, so far so good.

 

It happened once to me. Should I take my car in for service? (2010) It has 43,000 miles.

 

cyclopathic,

Was it the noise that sounded like someone with a hammer was banging on the interior of the hood (for 5 - 10 seconds) an about a 2-4 bang/second rate?

Did you do anything unusual, out of the ordinary prior to the event? The two times I've had it happen to me, it was because I was moving the car, using all electric and I shut the car down JUST as the gasoline engine was firing up.

Both times that happened, when I started it up the next time, I got the engine knock event.

 

I had the same exact issue this morning, exactly once and never again duplicated. The sound was out of character.

 

Did you smell gasoline? See any smoke, perhaps black, come out of the tailpipe?

 

Unless the OP lives in one of the states that enforce the California Emissions Warranty.

 

Can also be a fuel injector as it was in our case (sparkplug was tried first). Try a fuel additive.

 

Really curious to see if the intake manifold really fixes the problem. Curious also if there is any part of it that mounts to or somehow has an effect on the VVT-i controller.

 

Hi Pinto Girl

VVT-i is a completely separate system, and the logic for them is really sensitive, if there were an issue with the VVT-i getting stuck one way or another/not activating them it'd set a P00** code and MIL would be on..

Curious, to OP and any who have had the problem, what were the temperatures like? What area do you live in?

 

In our one occurrence of this anomaly on 9/20/10 I was able to check a nearby weather station's archives and learned the low temperature that morning was 58.5ºF with a dew point 40.5ºF. The previous day's high temperature was 80.4ºF. We are located in the Northern Sacramento Valley, California.

Since this single occurrence, and after reading PC posts, I have always thoroughly warmed up the ICE before shutting it down. So far, so good. However, since cold soak temperatures of 40ºF were not attained in my experience I doubt my service manager would replace the intake manifold.

 

I'll bet the next time you move your car and shut it down just as the gas engine fires up, it will trigger a "oh no" moment in your head.

It did for me. I'm glad I had my scangauge when I restarted later, because the engine knock threw an error code and I could clear it so I could drive the car without being distracted by the take car to dealer message.