Code P1128
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so my car had a check engine light and the code was p1128. when i give gas the car stutters and doesnt want to go anywhere. at high rpm the car dies down. i have replaced my 02 sensors and i have a new fuel filter that only a year old, i dont know what else it could be? any help will be great.
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CODE: P1128 - Fuel Trim Multiplicative, System Too Lean
my best bet will be the MAF Sensor
but go to webtech and you can get a some more info about that code
my best bet will be the MAF Sensor
but go to webtech and you can get a some more info about that code
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the code is for long term fuel trim system too lean. since you've already replaced the o2 sensors, here are some other things to check. check your vacuum lines connected to the intake manifold for cracks leaks or no connections. if you have the stock exhaust manifold make sure that it's not cracked and if so i think there's a bulletin or recall on them, so if you find a crack try and get it replaced for free. and check the evap canister purge valve (pcv) for continuity, power, and ground. (can be found between intake and driver strut towards the firewall (power is PINK & Ground is RED W/ BLACK TRACER), . hope this helps a little.
i'm going to shotgun an exhaust leak. LOL. good luck fing02.gif
EDIT** Looking at jay-m's post, he's right double check and make sure that p0102 (maf circuit low input) and/or p0123 (TPS ciruit high input) are not set as well.
i'm going to shotgun an exhaust leak. LOL. good luck fing02.gif
EDIT** Looking at jay-m's post, he's right double check and make sure that p0102 (maf circuit low input) and/or p0123 (TPS ciruit high input) are not set as well.
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thanks everyone...i will check those right now lol..will post back on what i find thanks again. fing02.gif
cheers
cheers
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If the air/fuel mixture under load is too lean for more than 30 seconds during two back-to-back trips, this code will be set and the Malfunction Indicator Light (MIL) will be turned on.
Details:
The code will be triggered if the following conditions are met:
Long term fuel trim value (multiplicative) is more than 1.23 ms for 30 seconds or more
Engine load is more than 2.0 ms (1.7 ms, 2.0L Tiburon)
Mass air flow rate is more than 8.4 g/s
Engine coolant temperature is greater than 158°F (70°C) [176°F (80°C), Accent]
Engine in closed loop operation
![](http://www.hmaservice.com/GRAPHICS/dt/dtc11281.gif)
Details:
The code will be triggered if the following conditions are met:
Long term fuel trim value (multiplicative) is more than 1.23 ms for 30 seconds or more
Engine load is more than 2.0 ms (1.7 ms, 2.0L Tiburon)
Mass air flow rate is more than 8.4 g/s
Engine coolant temperature is greater than 158°F (70°C) [176°F (80°C), Accent]
Engine in closed loop operation
![](http://www.hmaservice.com/GRAPHICS/dt/dtc11281.gif)
![](http://www.hmaservice.com/GRAPHICS/dt/dtc11282.gif)