jujuC6

Hello everyone, lately I have been experiencing mild shakes at idle & low RPM loads. Stepping on it = flashing CEL which goes away after a couple of minutes of driving easy. I have not had the chance to pull the codes but have anyone gotten this before? Will update with codes when I get the chance. Thanks in advance.

royclark

As you say, your first job is a vcds scan.

InfamousAvant

Once a code read is given, a determinant of guidance can be given. As of now it could be a number of variable possibilities.

jujuC6

Any advice before I bring it to my mechanic Friday? Thanks.

raj99

check the spark plug and coil packs, as step 1.

jujuC6

Replaced with new coil pack and spark plug on cylinder 4, problem persist. Old spark plug was dry and looked in decent shape, I decided to leave the new setup installed. My mechanic added seafoam through the intake and car felt a tiny better right after but problem still persist. After driving the heck out of the car in the highway power loss improved a little but the shakes are the same. My mechanic said, its must be carbon deposit and will perform the walnut shell blasting procedure 4th of July weekend. He advised not to do the seafoam again until after 1k miles. I am tempted to do the seafoam again, any reason why not? Anyone has done the walnut shells cleaning with positive results? Thank in advance.

raj99

if you already have carbon, seafoam isn't going to do much. Kind of like attempting to wash your car by throwing water on it...it'll remove some stuff, but 90% will remain.

You can carbon clean yourself as well...it's just a manual process and some basic tools:

jujuC6

My thermostat is operating perfectly but after seeing this video it really makes sense to change it there, should I even if it good now? How likely is it to go bad in our cars?

jujuC6

So, I heard back from my indy-shop with the expected carbon deposit issue but I also have a failed intake manifold flap and very likely needs new injector at cylinder 4. Unfortunately one has to buy the whole intake as the flap is part of the intake manifold and not separate. I found a couple of used ones in working conditions but afraid of the risk so I'm leaning towards new which is over 1k for the part. Can the flap be cleaned out or rebuilt? On a good note the engine has very good compression and is in great shape beside this of course. $1800 takes care of manifold, 1 injector, carbon cleaning and bad fuel pressure sensor. Decent price?

FL C6.5 Avant

i believe from reading other threads that the 3.2 IM flap is a fairly common issue. The design is really quite simple, but the ball linkage is prone to failure. check first and repair the linkage (thread is here or the other forum, don't remember).