nivlaman31

Hello, For Christmas a bought myself a 2004 C5 6M with only 14K miles. Completely stock. Car is nice, clean and always garaged by all owners. I am 3rd owner. I can tell the previous owners only really did oil changes so I changed the air filter, Diff, trans fluid, engine oil, and changed the belts to stop a squeaking. I also ran two cans of BG44K through it thinking the injectors may be dirty. Made no difference. The car runs basically flawlessly except when I come to stop lights the engine shakes hard sometimes enough that the whole car moves around. It idles right around 750 with a slight fluctuation up or down. It is not enough the throw a code for misfire. My first GM car so I am not sure if this is normal for C5 Corvettes. I am used to foreign cars that the idle is so smooth it is like a Swiss watch idling steady. So, my question is, should I change the plug and wires on it anyway because they are the originals and 16 years old? Also, I am sure the Mass flow sensor nor Throttle body has ever been cleaned. Any thoughts on this would be greatly appreciated.

Thanks so much, Al

scorpiofox69

Definitely clean the sensors. I also did plugs and wires shortly after acquiring my 04. Smoothed out after these housekeeping items.

C5 Diag

With the rough idle I'd clean the Throttle Body and MAF !!

nivlaman31

Thanks for the suggestions, I just got MAF cleaner and throttle body cleaner and plan on doing that this weekend. I got Iridium plugs and red GM wires on the way. I'll try to replace soon. I'll report back when I complete these tasks.

Thanks again.

C5 Diag

GM red wires are good !!...just make sure you push them on completely until you hear them click !!