i am just wondering should i be running a tune in the winter months or should i go to gm and get reflashed for the winter months .... will this lose my current tune from rob.....

my car is running really funny since the weather has change .... is this normal first winter with the car and i plan on running it through winter ... please help with any info possible...

 

you're going to be lean as hell if your car's tune isn't compensating for IAT. lean = knock = bad.

 

Do you have a wideband??

 

nope

 

should i get the gm flash then

 

If you have GM flash it youll loose your tune from Rob.

 

Just call Rob and let him know whats goin on . He would prolly update for free for ya . Whats the car doing exactly ? ...you can call me if ya want .

 

what is the car doin??

 

it is like backfiring in rpms going into the next gear like it is trying to hold me back from shifting.. only get it when i go wot when it is really cold out

 

there is a table that adjusts timing vs IAT which might have been modified, so you might be running to much timing, do you have any type of logging ability (HPT, aeroforce gauge)?.
As for fuel, I'm not sure if the vehicle has the ability to add fuel with colder temps, but it might be in the injector flow vs manifold pressure, as with colder temps the pressure is different.

 

Never modify, especially with forced induction, without a wideband. Get one asap.

 

nope dont have one ... is that the guage that everyone is talking about

 

A wideband is basically a unit that hooks up to a sensor, an O2 sensor (wideband sensor). This O2 sensor goes in your exhaust system with a bung to keep it in place, just like how your stock O2 sensor works but it does not interfere or have anything to do with your stock PCM.

Your stock O2 sensor is an narrowband sensor...basically, it can only tell if you're leaner than stoichiometric (14.7 a/f) or richer. I believe it tells by temperature of the exhaust against the sensor, I gotta look this up again. It can't tell exactly what your air to fuel ratio is.

A wideband will be able to read your air to fuel ratio to the "T". It will be able to allow your gauge to display the exact number (example: 12.5). When you start reading more on what is rich and what is lean, you'll understand what numbers you might want to aim for.

To give you a general idea, typically people with forced inducted vehicles want their vehicles to be very rich...in the 11.5 to 12.5 margin. This isn't for necessarily performance reasons but safety reasons. Your fuel helps keep temperatures down in your combustion chamber. More fuel means lower temperatures and less likelyness of some type of knock (detonation) occur. Detonation is basically an occurance of high temperatures causing an uncontrollable explosion, this could lead to engine damage of all kind of parts.

The reason people are "tuning" for the winter time is cause colder air is denser...to explain...denser air has more air molecules. The more air, the more O2 molecules present that can entering your combustion chamber and in turn this will change your air to fuel ratio, making you run leaner. So in the summer time, it's warmer, less O2 molecules in the air...so your tune might be great for that amount of air being seen cause you're supplying that amount of fuel for that time period and outside temperature. As seasons change, air density changes. If you've ever noticed that you have more power at night when colder than during the day in a normal car, you'd understand why.

Typically from factory, manufacturers like to have the engine run richer, boosted or naturally aspirated. Reason being? Like said, richer is safer but of course there are the degrees of running rich. There is a such thing as too much fuel (even though the term "rich" means more fuel than air hencing too much fuel)...this could result in flooding of the motor. Even with flooding the motor, bringing your car back to normal from a flooding occurance WAY cheaper than fixing a motor from running a lean condition which caused a bad detonation. It's safety versus power.

Overall, get yourself a wideband to make sure that you stay safe in your car and your engine keeps itself running longer. A wideband will also help incase there are any type of failures in your fuel system (bad hose, injector stops squirting fuel, bad fuel pump etc). It's for insurance and safety.

Hope this helped. If you have anymore questions, feel free to ask.

 

stage 2 + 2.8 + CAI + cold weather= lean=BAD