im looking at a 2009 cobalt ss/tc and the dealer said it has a tune on it but doesnt know what kind.

how can you tell which one?

he said that dejon performance done the car idk if thats a shop or what

thanks guys

 

My advice would be to forget about what tune is on it. Check if it has the GMS1 sensors, pictured here:



It's the Bosch sensor with the white and blue sticker. Just get the car retuned after you get it. BYT is a good source, though I'm happy to help you since you're local.

Also, I would advise a leakdown and compression test. I would never buy a used performance car without one. Open the oil cap and smell it. It should not smell sweet, like coolant. Those are the big ticket items that can happen. Other than that, this car is cheap and easy to work on.

 

If the dealer knows it's tuned don't expect warranty.

 

its a small car lot that is long way away, do you have to put a gms1 sensor on it before you can put any tune on it?

i would like to have a trifecta tune but yea i would still like to have a warranty for a little bit because it is a low miles car

thanks guys

 

gms1 sensors aren't required for any tune aside for the gms1 tune file itself. The sensors however can be used when tuned via Trifecta, or HPT though regardless. So finding the gms1 map sensors already installed doesn't guarantee anything as far as which tune you are running unfortunately.

 

how can you remove a tune?

i know that the trifecta you can turn on and off cant you?

sorry guys im new to forced induction cars and new cars period lol use to the old stuff

 

Any tune can be written over with the appropriate/compatable tuning software (HPTuner, Trifecta, SuperChips handheld, ect ect). The only iffy thing about going back to a stock tune or even an aftermarket tune is being absolutely sure that you still have the stock 2.5bar sensors in place. The stock tune file is not compatable with the 3bar map sensors, unless your tuner if fully aware that you have the 3bar map sensors installed that is.

If you look at the pic posted above, the sensor on the right side of the manifold is the map sensor. Notice that it has only 1 bolt securing it down to the mani.... this is the gms1 3bar map sensor.

The stock sensor on the manifold will have 2 bolts securing it down. This is basically the easiest way to identify the 2 sensors from one another.

 

If u don't mind me aski. Where is the car located? If its. Long island ny. And red witg less than 25000miles it was probably mine cuz i just sold it a couple weeks ago

 

from the pics it looks like it has the 2 bolts

 

You must be accidentally looking at the wrong thing then. The sensor I am refering to is the black bosch sensor with a white/blue label on it which is on the front right hand side of the mani in that pic. It definitely has only 1 bolt ear to secure it to the manifold..

 

can i just change the sensor with a stock one or a gms1 to remove the tune?

thanks guys

 

no im talking about the pic of the car im looking at

 

Just swapping the sensors to a different sensor won't do a thing to change the tune, and actually wouldn't be a very wise thing to do at all. Both the 2.5bar and 3bar maps use different voltage scaling in the tune to register boost signal.

 

it still has the stock map sensor it has 2 bolts holding it down ill post pics of the car soon couldnt get it this weekend bank was closed

 

 

is that the stock map sensor?

Thanks guys

 

Yes.

 

Am I seeing a BoV under there? If it is, I'd bet it's an HP tune. Still could be Trifecta, but you'd have to ask Vince to know.. just give him the Vin # and he can look it up. If it's not his, then it's most likely an HP tune. My 2 cents

 

k what is vinces username?

 

VinceTrifecta

 

thanks

how could you tell if it dont have a tune?

he said believed it did but alot of people will tell you that to sell it will it not go over a certain boost range?

thanks

 

Generally speaking, the stock boost range will be from 14-16psi but a lot of that is subjective to climate and altitude and can change with either. With the stock sensors in place you can be absolutely sure that the car does not have the gms1.

You can always contact Vince @ Trifecta and ask him to run the VIN to see if that car is in his system. The only real way to know for sure is to have someone who knows what they are looking at plug into the vehicle with hptuners and read the ecm. If they can't read the tune file then most likely it's Trifecta tuned, but if they can read it then they can tell you exactly what (or if any) maps have been changed and/or altered.

 

Its pretty safe to say that it's definitely tuned........If it wasn't tuned it prolly would run like crap ...... Adding a BOV to a stock tuned car would really mess up the Air/fuel ....then add an AEM intake on top of it and odds are it would be setting a off a engine light with fuel trim codes.

 

This ^
Hence, why I said it has to be tuned since there's a BoV in there.. no way it'd run half decent without a custom tune with the couple mods we can see just from the pics. Vince is away for at least a week, find an HpT guy if u know one locally, and do what 09CobaltSS1 said.. That's your best bet right now imo. If it's not tuned, it's going to run like total ass, so make sure you drive it b4 you buy it.. which anybody should do b4 seriously buying any car, new/used, it doesn't matter.

 

yea i know exactly i believe they are something wrong with it because the dealer don't want me to drive it because he wanted me to wire him the money and deliver it and i said no and he came in and hauled it on a car hauler and didn't want me to test drive it but he started it and it sounded fine.

if it has a tune and you take it to the dealer to have it removed so you can keep your warranty?

I need a warranty because i am going to use it as my DD

Thanks