10mpg because of a tune?

[ChriSS_MD]

I have posted pictures and a startup video in my welcome thread. Basically, I bought a modified 2011 w/36k Friday from a dealer. It has at least a CB and Y. The dealer said it and stock headers, but I don’t think so. The SES is on because they said it’s an 02 issue.

I’m sure it needs a tune, but I need to find someone local to OKC.

The dash computer is telling me that I’m getting 10-11 mpg. I filled up after I left the dealer w/93 and have put roughly 70 miles on her. There’s no was it can be that low, right? I drive country roads at 50 mph because of a storm and the around town.

Would a tune affect it that bad?

FYI, I found out the remote start doesn’t work if you have a SES light on.

[Rob10CamaroSS]

No Way in hell you should be getting 10 to 11, my ZL1 has like 750 Flywheel HP and gets over 20 MPG "IF" I drive normal (which I don't but I did once to take this picture, LOL)

Nice Camaro with a very clean engine compartment, CONGRATS & WELCOME
With the SES Light on, no Remote Start, and something going on with the fuel economy (or the reading of it), I think you should let them look at it while you have a wrrnty. On a 70 mile drive there is no way it should be showing an average of 10 to 11, especially if your saying you were driving 50 mph in a storm

[Vegas Bound]

#1 - those are headers not stock exhaust manifolds.
#2 - if the headers were put on without a tune or the dealership reflashed a stock tune, you will receive a CEL.
#3 - Call Anything Automotive Performance in Denton, TX and set up an appointment for Calibrated by Karger to tune your car.

[CamaroBarb]

If your car has cats on it they are going to get cooked in short order if you are only getting 10mpg.

[sscamaro]

With the mods listed below, I get 19 mpg around home and 24 mpg on a trip.

[ChriSS_MD]

Originally Posted by CamaroBarb

If your car has cats on it they are going to get cooked in short order if you are only getting 10mpg.

No cats. They said that’s what was throwing the code. Thanks for the help guys. I’ll call AA in Denton tomorrow.

I’m an old LS1 guy who has the same bolt-one and a Yank SS4000 and got decent gas mileage.

[InFiD3ViL]

Yes it is possible, if the tune is off a bit.

With my L99 (AFM disabled) before the engine swap and tune, I was getting 18 mpg. After the swap with the LS3 (Stock cam) and a new tune (same tuner), I am getting exactly 10.6 mpg, over 986 miles. Only difference in mods is my heads are now very slightly milled at .015

This is not my tuners fault though. I have been aware that the tune is on the rich side and he told me to send him a datalog so he could dial it in. Only reason I have let it go is that I wanted to make sure I fully seated my rings before he adjusted the tune. It's not even that rich. I am averaging between -5% to -11% LTFT on both banks off idle. At idle it is at 0% or right around there. But it is enough that I am guzzling down gas. Well, that and the fact that my engine builder told me to drive it like I stole it for the first 1k miles. But, I have not really been driving it that heavy footed. Not much more than my L99 to be honest. I just made sure to get a few good WOT pulls in, but drive it normally most times.

But...it is likely you have other issues if you have a CEL light on. There may be a very specific reason you are running rich and the tune may be fine. Get your codes scanned, see which sensor it is and fix it. I have had issues in the past on this car with it being pegged at -32% rich on one bank due to a slow or failed O2 sensor and it never generated a code. I could see it in the O2 voltages for that sensor.

[SSE 4 2SS]

I would venture this is your average fuel economy, not a spot view. Unless you reset it, then you are seeing a long term fuel economy average.

If you have a bad O2 sensor, then you could be heavily over-fueling that bank. With the stock manifold and a cat back system, (Y ?) "Y" pipe, you don't need a tune and can still get good fuel economy.

Drive it for a bit longer where you know how it's driven, have the O2 sensor checked, and replaced if it's bad, and reset the fuel economy average.

[ChriSS_MD]

With the new Y pipe, they deleted the catalytic converters and O2 sensors. I’ve reset the trip and average fuel meter. I’ll see what happens this week when I drive more.

[SSE 4 2SS]

Originally Posted by ChriSS_MD

With the new Y pipe, they deleted the catalytic converters and O2 sensors. I’ve reset the trip and average fuel meter. I’ll see what happens this week when I drive more.

They should have only deleted the rear O2's... Yes you might have a fueling issue if they didn't tune to turn those off or disable them or hpwever that's dealt with...

[InFiD3ViL]

Chris, I am not sure if you misspoke or not, but your car should not have a Y pipe in any configuration. It looks from your original picture that you have long tube headers. If you have a Y pipe installed, you have other issues as these cars are not made for Y pipes. Take a look under the car and let us know when you get a chance.

These cars are designed to have two semi-independent (H pipe or resonated H pipe from factory) exhaust paths, or what essentially looks like a true dual setup, even on the V6's. They are not designed to have the manifolds or headers merged into a single exhaust via Y pipe. In stock form you would have a seperate upstream and downstream O2 sensor for bank 1 and the same for bank 2, for a total of 4 sensors. When long tube headers are added, many people will 'delete' the rear sensors and have the reporting tuned out so as to not trigger a CEL. I am really hoping a dealer did not weld or connect in a Y pipe with a single cat back exhaust and somehow try to rig the O2s on this car. If you simply misspoke and it is an H or X pipe, that is something entirely different.

Let us know what you find.

[SSE 4 2SS]

Originally Posted by InFiD3ViL

Chris, I am not sure if you misspoke or not, but your car should not have a Y pipe in any configuration. It looks from your original picture that you have long tube headers. If you have a Y pipe installed, you have other issues as these cars are not made for Y pipes. Take a look under the car and let us know when you get a chance.

These cars are designed to have two semi-independent (H pipe or resonated H pipe from factory) exhaust paths, or what essentially looks like a true dual setup, even on the V6's. They are not designed to have the manifolds or headers merged into a single exhaust via Y pipe. In stock form you would have a seperate upstream and downstream O2 sensor for bank 1 and the same for bank 2, for a total of 4 sensors. When long tube headers are added, many people will 'delete' the rear sensors and have the reporting tuned out so as to not trigger a CEL. I am really hoping a dealer did not weld or connect in a Y pipe with a single cat back exhaust and somehow try to rig the O2s on this car. If you simply misspoke and it is an H or X pipe, that is something entirely different.

Let us know what you find.

This...


I read "Y" pipe and was seeing "X" pipe... Thanks for clarifying this... I certainly hope they didn't put a Y pipe exhaust system in....

[ChriSS_MD]

Originally Posted by InFiD3ViL

Chris, I am not sure if you misspoke or not, but your car should not have a Y pipe in any configuration. It looks from your original picture that you have long tube headers. If you have a Y pipe installed, you have other issues as these cars are not made for Y pipes. Take a look under the car and let us know when you get a chance.

..When long tube headers are added, many people will 'delete' the rear sensors..

Let us know what you find.

I have not been under the car yet, but I figured it had a Y pipe like my 99 SS. This was more of an impulse purchase and I hadn’t done much research in the Gen 5/6 models. I thought I’d buy a truck to replace my totaled Accord..but a modified ‘11 w/36k was sold me.

[SSEssence]

Your car definitely has long tube headers from that photo. If there is no CEL, then it probably already has a tune. It shouldn't be getting 10 mpg. My car has long tube headers, x pipe, muffler delete, and a stage 2 cam and im averaging 16.2 mpg.