Rough Idle

[OGLaughtzalotzz]

whats up everyone!
so when i purchased my p5 i saw that the idle was rough. so reading around here i saw that it had the same symptoms of a bad EGR valve. so i replaced it as well as the spark plugs but got the same result. what else could i change or adjust?

 

[CheeseHelmet]

The most likely cause of rough idle is a cracked air intake tube (the one that goes from the MAF to the throttle body). Take off the tube and examine it carefully, I wouldn't be surprised if you found a few holes in it.

If that's not issue then it might be a problem with your coilpacks but in that case the check engine light would probably be on.

 

[OGLaughtzalotzz]

will do...hopefully the weather clears up

 

[i12drivemyMP5]

Could also be coils but those usually throw misfire codes.......

 

[OGLaughtzalotzz]

just got a misfire code...i beleive its P0300 when my ebay intake arrives i'll see how it idles then go on from there

 

[CheeseHelmet]

just got a misfire code...i beleive its P0300 when my ebay intake arrives i'll see how it idles then go on from there

You probably have a bad coilpack.

 

[bigpturgeon]

Just get the packs and the wires dude thats your problem.

 

[OGLaughtzalotzz]

just a quick update...i replaced the coils and wires and plugs and i'm still getting misfire codes...thoughts?

 

[CheeseHelmet]

Could be the EGR valve, is your idle still bad?

 

[BRIAN_MP5T]

I assume Plugs were replaced?

 

[CheeseHelmet]

just a quick update...i replaced the coils and wires and plugs and i'm still getting misfire codes...thoughts?

I assume Plugs were replaced?

It appears so.

 

[BRIAN_MP5T]

This could be anything from, bad gas, Plugged Fuel Filter, Bad Grounding, Clogged Injector, Vac Leak...

Literal One of 25 things.