Update on Page 2

So I woke up and started my car this morning and the idle is extremely rough. Actually anywhere below about 1100 RPMs it is very loud and rough. This hasn't happened before and it was fine driving home last night at around 1:30am. The car still seems to drive fine, but this sounds like a bad omen. Has anyone experienced this before?

My first though was an exhaust leak but it doesn't seem to get louder with RPMS and all the connections seem solid. I make a quick check of all the IC piping as well and it seems solid. I haven't even drive the car hard at all in weeks....

HELP! Any thoughts? What should i check? It almost sounds like a cylinder went out bu the power still seems fine. It's almost like my cams are out of phase or imporperly timed, but I installed those over 2 months ago so that would be pretty odd...

List of things Checked so far:
-FPR line
-IC piping
-Exhaust pipes after DP
-o2 Sensors

 

Unlikely, but check the vaccum line from the PCV to intake manifold. Mine blew off once and caused a pretty nasty idle. It may even have a cut or slice in it. Who knows? Check it especially if you have a catch can, for it may leak or the hose may have disconnected. Just an idea :-/

 

Took a look and it looks all good there. I checked all the other vac lines I could see as well and they look fine. I am resetting the ECU right now just to be sure but I doubt that will do much.

Any other suggestions?

 

Also I forgot to add, it was about 50 today, so no extreme temps...hell it's idled better in -5 deg weather.

 

Did you check all the vac lines behind the intake manifold? they are the ones for the EGR. there are vac lines in the passenger side and on the drivers side that can go loose.

 

Yeah I looked all around there and they were all hooked up, unless one of them developed a tiny leak overnight.

 

vacuum is at 5-7 at idle, it used to be 10-15

 

hows your boost when driving?Have you had a tune after all those mods? If your getting less vacuum then you have to have a leak somewhere. try doing a complete leak down test first. http://www.cobbtuning.com/info/?ID=3481

 

Maybe it's your camshafts, i have HKS 272's and it idles really rough in the morning...

 

camdhafts never made it do this before, plus its a constant thing even after warm. I did get a tune and my boost is still right on target. This is really crappy. I an going to check over all the vac lines again and see if I can find something. Would something have fallen off I wonder...

 

good luck man wish i could help more

 

fouled up spark plugs from recent tune?

 

Well I pulled the plugs, they seem OK.

Another new development, when I go WOT and get to about 4500 rpms the engine drops back about 3-400 rpms and then will continue to go up as normal...

HELP

 

Misfire possibly?

 

It's just odd because it started for no reason last week and it's still idling like crap and doing this strange stuff....