Anyone drive their FI car on a stock tune? wondering if whats happening is normal
#1
Anyone drive their FI car on a stock tune? wondering if whats happening is normal
i havent gotten around to tuning but ive been driving the car to make sure everything is running right
so here are the issues, at steady state cruising, as in staying in gear at a certain rpm for a while the AFR just drops like a rock from 13.5 all the way to 10.5-10.1, then the car bucks and hesitates like crazy till i switch gears or let off the gas
so i read the 02 sensors and one was off so i figured it was an exhaust leak. i fixed the exhaust leak and now the AFR still drops while at cruising but it stays around 11.0 now and the car wont buck or hesitate but i can feel it trying
is this normal because of the stock tune and the turbo? as in the MAF is reading the turbo and the MAP reading the intake manifold so it dosent know what to do?
also when i let off the gas the idle takes a while to fix itself it flutters till it catches itself.
i just want to make sure the car is fine before i start tuning
(also i might as well mention that the long term fuel trims are maxed out, thats what im worried about, are they maxed because of an exhaust leak, or because a stock tune cnat figure out what to do with the turbo)
so here are the issues, at steady state cruising, as in staying in gear at a certain rpm for a while the AFR just drops like a rock from 13.5 all the way to 10.5-10.1, then the car bucks and hesitates like crazy till i switch gears or let off the gas
so i read the 02 sensors and one was off so i figured it was an exhaust leak. i fixed the exhaust leak and now the AFR still drops while at cruising but it stays around 11.0 now and the car wont buck or hesitate but i can feel it trying
is this normal because of the stock tune and the turbo? as in the MAF is reading the turbo and the MAP reading the intake manifold so it dosent know what to do?
also when i let off the gas the idle takes a while to fix itself it flutters till it catches itself.
i just want to make sure the car is fine before i start tuning
(also i might as well mention that the long term fuel trims are maxed out, thats what im worried about, are they maxed because of an exhaust leak, or because a stock tune cnat figure out what to do with the turbo)
#5
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im not sure that anyone has tried running that on a stock tune. its kind of silly to pay that kind of money just to mess it up like that. at least dont come into boost until you get it tuned
#6
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i drove my STS kit with a stock tune, and the car ran like ****. i was lucky to make the 5 mile drive from my mechanic's to my house. if you are like me, you will never know what the real problem is until you take it to the tuner. the most random thing could be wrong, and that is why the car is running like ****. but the stock tune was designed for the stock car. the turbo makes the maf/map values different because the pressure is higher at a lower RPM. i am willing to bet tuning will solve most of your problems.
#7
Originally Posted by RooRnZ28
i drove my STS kit with a stock tune, and the car ran like ****. i was lucky to make the 5 mile drive from my mechanic's to my house. if you are like me, you will never know what the real problem is until you take it to the tuner. the most random thing could be wrong, and that is why the car is running like ****. but the stock tune was designed for the stock car. the turbo makes the maf/map values different because the pressure is higher at a lower RPM. i am willing to bet tuning will solve most of your problems.
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#9
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You're asking for it, seriously...
There are those who are prepared for FI, then there are those who will have to build their **** 3 times. Which one are you?
There are those who are prepared for FI, then there are those who will have to build their **** 3 times. Which one are you?
#10
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I just took my car to the dyno. Mine was running just like you are saying yours did. I thought I loaded a Predator tune into it, but something didnt go right. I installed new plugs when I installed my supercharger, and installed 45lb injectors as well. By the time I got to the dyno the plugs were fouled, and the back bumper was black from running rich.
With the bigger injectors, its dumping way too much fuel in and making it run rich!
You could ruin your plugs (if you havent already) and your o2 sensors.
Get it tuned before driving it anymore!
With the bigger injectors, its dumping way too much fuel in and making it run rich!
You could ruin your plugs (if you havent already) and your o2 sensors.
Get it tuned before driving it anymore!
#11
If you are running larger injectors you might end up washing the cylinders/rings and ruining your motor...
I wouldn't have even FIRED the car up without a base tune with IFR changes in place...
I wouldn't have even FIRED the car up without a base tune with IFR changes in place...
#13
ok let me clear up a few things:
i have a tune for the injectors, i have a wideband to watch the AFR, and ive datalogged the hell out of it on HPtuners to make sure the car wont blow up
i am not florring it i am just driving, and ive made sure nothing bad can come out of it being driven. i am not driving it blind and guessing if its ok
i just wanted to make sure that what is happenign is normal or becuase i have an exhaust leak etc. because ive already found one exhaust leak just from datalogging.
so please stop telling me i will blow up my motor, just let me know if what is happening is becuase of a problem or because it needs a tune.
i jts want to make sure the car is ok before i start tuning because then it will be harder to find the problems
i have a tune for the injectors, i have a wideband to watch the AFR, and ive datalogged the hell out of it on HPtuners to make sure the car wont blow up
i am not florring it i am just driving, and ive made sure nothing bad can come out of it being driven. i am not driving it blind and guessing if its ok
i just wanted to make sure that what is happenign is normal or becuase i have an exhaust leak etc. because ive already found one exhaust leak just from datalogging.
so please stop telling me i will blow up my motor, just let me know if what is happening is becuase of a problem or because it needs a tune.
i jts want to make sure the car is ok before i start tuning because then it will be harder to find the problems
#14
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Go get the car tuned. there isnt anyway to tell if there is a problem or not because the car hasnt been taught what to do with the positive pressure being forced into the engine. The car coudl seem liek it has a problem when all she needs is a tune.