Dealership says CAI is the problem...? (RESOLVED!)

[HarryNW]

I purchased my 2013 2SS/RS 7 weeks ago at the Bill Pierre dealership on Lake City Way in Seattle, WA. I almost immediately felt like the idle was a little rough and there was some obvious hesitation and bucking at low RPM, especially on a cold start.

Being my first real muscle car, I thought this might be normal. I proceeded with a few trivial mods: F8 Fuse Pull for Dual-mode exhaust, C.A.I. CAI, Skip-Shift Eliminator and the Octane Fuel Correction. I also checked my MAF for "weak/strong" and (a week after the CAI install) thoroughly cleaned the MAF with MAF cleaner.

Still, I continued to have rough idle, hesitation and bucking in lower-rpm, especially in the morning.

I called the service manager at the dealership about it and he said to definitely bring it in. We agreed the best plan was to drop off the prior night to allow the service team to see how it looked on a cold start, so last night I dropped it off. I told him to be sure they test-drove it, as the rough idle was subtle, but the hesitation/bucking was completely obvious in a test drive.

This morning by 10am, the service manager called me to say that there were no engine codes (we already knew/discussed that previously) and that they "could not properly test the car until it has the after-market CAI removed". I asked if they even test drove it and he said no. I insisted that the CAI would not cause this type of behavior and re-iterated the importance of test driving. He said there was nothing more they will do to test/troubleshoot the car until I remove the CAI, but would ask someone to test drive it.

As this was my first visit to the service department, and because I am new to most of this, I did not want to burn any bridges and agreed to come pick up the car and schedule a new drop-off for this Sunday night, giving me time to put the stock air filter back on.

However, by the time I got to the dealer to pick up the car, I had digested how much effort it will take to swap out the CAI and frankly felt pissed that I would go through this effort only to prove to him that this is not a CAI issue. He mentioned that they took a short test drive and did not notice any bucking.

I later had by brother-in-law (big-time motorhead, big mustang customizer) drive the car and he immediately noticed the idle and hesitation. He was actually able to show me that even at higher RPM, if I simply kept a stable RPM at 3,000, the engine was missing/hesitation rather than maintaining a consistent run. He said that if the dealer was not willing to put it on the computer, that a local speed shop could probably tell me exactly what was wrong in an hour or less, without actually applying a tune, but it would run a few hundred bucks.

My current plan is to put the stock air filter back on, replace the F8 fuse, take it back to the dealer, and see what they say.

Any thoughts/feedback?

------------------------------
Update: July 16th - Bottom Line: Move the Window Fluid Reservoir

Per the thread history, I had finally identified that there was something about the CAI install that caused the hesitation/bucking - I replaced the stock AF and the issue disappeared. Tonight, I re-installed the CAI. As I did so, I was staring at the C.A.I. heat-shield-box and I am thinking - where is the airflow? The stock AF has major open routes from beneath the engine and to the sides of the AF arm. When contained in the CAI box, the fluid reservoir consumes nearly every inch of open area beneath the CAI filter.

So I decide to leave the CAI plexi-glass cover off the box (it leaves a scant 2 inches of clearance to the underside of the hood), close the hood, and go for a little drive. Bingo, no more hesitation/bucking. I return, re-add the cover, and test drive - noticeable hesitations, especially in the 2000-3000 RPM range under modest acceleration. I return, remove it again, test drive again, no hesitation in acceleration.

Just ordered the relocation kit for the fluid reservoir, but will keep the CAI cover off until then.

Next, I installed the VMAX Ported Throttle Body. I can see why people have been excited about this - obviously you cannot sense the few HP gain, but the VMAX PTB clearly provides an improvement to throttle response. It now leaps out when I punch it.

My bottom line: I should have read more about various brands of CAI and their recommended installation tips - even though C.A.I. does not specifically call out the relocation of the fluid reservoir, it should be highly recommended up front. There are some other posts here that recommend doing this, and even go so far as to say that adding this type of "boxed" CAI without relocating the reservoir is a step backwards. I can now wholeheartedly agree.

[AdamZ]

You're running 91-93 octane right?

You should be idling between around 500-600 rpms

[HarryNW]

I ran the dealership fill down to fumes and have run nothing but 93 Octane for every fill-up.

To be clearer about the idle, it is subtle - it remains at 500, but every second or so it almost sounds like it is skipping a cylinder. It actually sounds like a classic camaro on the 1/4 mile line with a slight miss, but should not be like that for a stock build. I actually think it makes the car sound mean. If not for the hesitation/bucking I would not have said a word - there are even other posts/thread here that talk about the LS3 and a "rough idle", but they do not mention the hesitation/bucking.

To be fair, I think my thread title is a little off - it should be "Dealership says it cannot troubleshoot car with the CAI" - regardless, it just seems like they took an easy out once they saw the CAI. Why not do a computer check and a cursory check of the main suspects, like timing, compression on each cylinder, etc.?

[seattlemichaud]

What dealer are you attempting to have it serviced at because I am having issues at a Seattle area shop as well.

[AdamZ]

It just sounds like a fuel deal too me. Do a fuse pull and see what happens. Start with the little solutions

[HarryNW]

Have done the Octane (5/20/trunk ECM) fuse pull, about 2-3 weeks ago - made no difference.

Servicing at the same place I bought it - Pierre Chev on Lake City Way.

[Scott@Bjorn3D]

How does the car do when warmed up. These cars have many sensors and they have to get to operating temp before the car runs smooth. If I start my car up in the morning and let it run 5 minutes she is ready to run like a bat out of hell. But if I just start her up and drive he it takes about 3-4 miles to have her ready to run great. This is usually only after sitting all night.

I have CAI, VMAX Throttle Body. My old L99 2010 was the same way.

[seattlemichaud]

Originally Posted by HarryNW

Have done the Octane (5/20/trunk ECM) fuse pull, about 2-3 weeks ago - made no difference.

Servicing at the same place I bought it - Pierre Chev on Lake City Way.

Not where I got mine. Good luck.

[HarryNW]

Hmmm, sounds about the same Scott - I still notice slight hesitations at running temperatures, but not nearly as noticeable like it is on a cold start.

Have my VMAX PTB sitting in a box awaiting the results of this little investigation... Clock is ticking to get that swap credit in time...

Daily drive car for me, and just frankly surprised that this much technology needs a 60's-era warm-up period, but if the veterans here on C5 agree this is a matter of warm-up time, then I will shelf the issue until I get a first tune...

Anyone else think this is a warm-up period issue?

[OHIOSS]

I have a 2010 w/ LS3 and I don't do any kind of warm up. I start it, wait about 10 secs for the oil to get to where it needs to go and drive. I have no problem with rough idle, and no bucking at any speed. I have never heard of anyone going through a warm-up procedure until I read this.

Russ

[i2disturbedSS]

Just take it somewhere else.
And check if the air intake is on correct and snug.

[Del's12SS]

You may want to ask this question in the V8 bolt on section of this site.
There are a couple of guys over there that know these motors.....

BTW, Thanks for posting this, I look forward to hearing more on this.
Mine idles a little rough in the morning..... I don't let it "warm" up, but I do take my time before I leave the drvieway.

[BigPopa71]

On a car that new what you should have done was make sure they fixed your car before modding. I'm not attempting to fix anything on a new car by investing in mods. The mods are for my enjoyment. With the amount of money you paid you deserve to have a perfect running car without worry. Now you are kind of at the mercy of the dealer you choose to provide you with service. I would be more upset with myself right now than anyone else... Good luck and try a new dealer and see of they want you to take the CAI off as well.

[SlingShot]

What brand CAI did you go with ?

I know on my car, it always runs like crap when it's started until it warms up. That's just typical of the LS3, and so is the somewhat rough idle. I really don't think you have any worries unless you went with a K&N CAI.