fuel injector cleaning will amount to them pouring fuel injector cleaner into the gas tank. Without any DTCs, it could be anything.

 

I wouldn't try cleaning the throttle body. Too many sensitive electronics in there. It's not like the old days..

 

With the way the PCV setup is on these cars (at least my 2012) I doubt it's your throttle body. My 2012 has a little sponge in the airbox that will catch most of the goo that is introduced to the intake tract from the PCV.

On every fuel injected car I've see these days, the throttle plate is close to, if not fully closed at idle. Idle is controlled with an Idle Air Control (IAC) solenoid that has a built in range of adaptability that allows for idle correction.

If it was my car I woud just go through real quick and spot check:
air filter/plugs/sensors.

 

Pull off the air cleaner from the intake. Then run the engine and spray TB cleaner in there a little at a time and rev it to burn off the deposits. This worked for my Patriot.

 

As hunter mentioned, you can clean it that way, but you'll want an assistant to work the gas pedal for you. I would also run a tank or two of gas with a double dose of fuel injector cleaner added. Seems our injectors are a little more prone to clogging and spray degradation then other models.

 

So i went to the dealer today, they suggested the following

Emissions (Decarbon) $149
Throttle Body $120
Fuel Injection $115

They said it will help with the stuttering/idling issue issue when at the stop lights.

Any recommendations??>?


They also recommended filling up a full tank of Octane 91 (premium) and running it all to burn off the carbon.. if it makes sense?

 

You can de-carbon the engine yourself using just water. Find an old spray bottle, one that sprays really well (or purchase one from a garden center, those usually pump a good quantity of water per pump). Pull the intake hose from the airbox and have an assistant rev the engine to 2500-3000 rpm. Start spraying the water into the hose as fast and furiously as you can. You want to start seeing white smoke out the exhaust. This will essentially steam clean the combustion chambers.

The 91 octane suggestion is probably only because the higher test fuel usually has additional cleaning additives in it. Throw in two bottles of fuel injector cleaner and run the engine hard through out the tank.

 

I've been having a similar rough idle when warm, so I've been following this thread.
Ran a can of the injector cleaner through the tank, and have another one for the next tank. I decided to finally change out the plugs too. The miles crept up on me and these have about 45,000 miles on them.

With just a little driving around today, there doesn't seem to be much difference. But I can at least tell the plugs were due to be changed out.

 

SeaFoam

Link

 

SeaFoam now makes a spray. Cool!

 

I Seafoamed my Cherokee and not very long after had to replace the catalytic converter. May have been a coincidence, though I had heard warnings that it might happen that way if I did the Seafoam thing.

 

It's possible you just have some water in the fuel tank. Warm, humid days and cold nights will build up condensation on the inner tank walls.

 

I removed my intake manifold this weekend because I was having issues with the flapper valves. My whole intake, TB included, was absolutely filthy! Everything was coated with what appeared to be a tar film, but it all came off easily with carb cleaner.

I wasn't having idle issues, just the DTC caused by the valve problem, so it ran fine before and after the surgery. I just wanted to point out that these things can get dirty (mine has over 90k miles). Also, removing the intake, or even just the TB is not a job I want to do again. I was able to R&R everything in an afternoon, but not fun.

 

re: tar like film

Yeah... My '07 Patriot with about 68K miles on it has been at the dealer for the last couple days, getting a new transmission. (Had the CVT transmission whine noise, and they're swapping it out under my extended warranty for a $100 deductible.)

They just called to tell me the mechanic noticed a "tar like substance" all over the inside of the throttle body, while they had things taken apart, and recommended a cleaning (for an additional $149). I was hesitant, thinking this was just another scheme for the dealer to make some easy money. But I decided to just go ahead with it. And posts like yours make me lean towards thinking it might have been wise...

I know a while back, I had a problem where the guys at a quick oil change place forgot to put my cap back on, and oil splashed all over the engine. I'm wondering if that caused a lot of oil ingestion that gunked things up.

 

kingtj - I doubt it, unless it fell into the intake tract.

 

I wonder what is causing all this gunk to build up... I mean, i can see this happening in vehicles that are getting on a decade old, but seriously? Something is up...