Well, after all is said and done, I had the fuel pump replaced and it's still making the one second flutter on cold starts. What could it be?

 

I won't even begin to enumerate on the string of profanities that just sent two cats flying out of the office, oh how I wish you were kidding Tyler.

Still doing exactly the same thing, even with the pump being diagnosed as bad and replaced, obviously its going to have to go back.

Do you know if they had it on a real time scope to look at fuel pressures and cylinder firing events?

I am so sorry that this is an ongoing thing, but I'm mystified as to why, time to dive into the manuals again....crap!

***Edit, just went back and I saw where the tech Marcel diagnosed the problem by ear just as the tech's here did, but did they follow up and do the full diagnostic tree including the use of a diagnostic scope? You want to talk to the service manager tomorrow and see what they are prepared to do, not following all of the diagnostic procedures is a "no no".***

 

lol. Mike, I would say they didn't have it on a scope. I get the impression from them that this is normal. There was a girl who brought in her Cobalt SS on Monday as well and she has the same issue. She was told by the dealership, that's it's normal! To me it's not normal, but then again this is my first turbo engine.

 

I'm just so sorry that the "cure" wasn't the "cure" after all, even though you probably did have a failing fuel pump.

If it were mine, I'd insist that it be hooked up to a real time diagnostic scope, with a tech that knows exactly what he's doing as far as diagnostics are concerned.

Its not normal in my book, or in the minds of the techs who listened to it here in NC, I really feel like I let you down man.

 

It's all good Mike, the fuel pump was an issue, so that is now solved. I'm not finished getting to this problem. I'm going to have to get a dianostics done eventually. No let down here.

 

Thanks man, my heart really sank when you said it was still misbehaving.

 

Mine has been doing it off and on for a while now. 39k on the clock and i need to get it checked. so I can generate a paper trail for warranty, even if it's determined to be "normal".

I agree with you. My first impression was and still is cam chain tensioner. I've heard it in other vehicles with chain and hydraulic tensioner. It is only heard after sitting overnight and it's very momentary upon startup. Not even 2 seconds. It always runs fine and I don't notice any ill effects.

Oil changes at 50% on the oil life monitor with synth blend oil, no metal particles have ever been noticed in the oil.

 

Can you get a sound clip of the noise?? Does it sound like this?

http://www.youtube.com/watch?v=zQGee4D2qtM

Mine sounded just like this and the noise was linked to the serpentine Belt. I know some people are going to say no way.. But I am 2 for 2 fixing this sound, by replacing the belt.

 

Good clip, that's the noise. Mine does not last even that long. It sounds just like chain slap, but a belt could do it, too. I think Silverfox on another thread said the belt was the fix for him and his issue started way earlier than ours.

 

Mine was the belt , changed it out with a Good year gato back , no more noise, now mine is not a Turbo SS but sounded like the same noise