Hi everyone, new to the forum, this is a long one so apologies!
I am having rough idle issues which I have been battling for a while now. Just off the bat here are the symptoms/codes/mods, I will follow with things I have tried to fix the issue. I know there are threads similar to this but none have solutions that have worked yet :/. So here goes:
Mods:
-sports cat
-ramair intake
Symptoms:
-idle misfires on cylinders 1 and 3 sometimes almost to the point of stalling but not very often
-plus fuel trims only at idle
-minus fuel trims when maf unplugged/runs better. Again only at idle.
Codes:
-P0133 02 Sensor Circ., Bank1-Sensor1:Slow Response (this code is normally no activity detected rather than slow response)
-P1103 Bank1-Sensor1, Heater Circuit
erformance Too Low
-P1539 Clutch Pedal Switch: Implausible Signal
-it also has a brake module malfunction code which i can’t remember what it is exactly but can get that today if that would help. This doesn’t present a light on the dash though.
Now, you might say replace the o2 sensor however I have replaced it twice. There is a chance that it is the wiring however when looking at VCDS the sensor is working and trimming the fuel, it just shows a code that says it has low or no performance.
Anyway here are fixes that I have tried.
-replaced o2 sensor
-fixed all vac leaks including; deleting the SAI with blanking plate, rocker cover gasket, oil cap and a check valve which had split. The car was smoke tested to find these.
-new genuine bosch MAF sensor.
-4 brand new spark plugs.
The car runs better with the maf unplugged, and again you might say to replace maf but the maf sensor is reading within the specified limits and not malfunctioning. When unplugged the fuel trims go from +25 to -25.
I’ve also rearranged the ignition coils to see if the misfire moves with them but it doesn’t so not ignition coils.
The previous owner had the car mapped and had a straight pipe where the o2 sensor was removed entirely and the tuner 0’d the table of values for the o2 sensor to “delete it”. I’ve had that taken off and put a sports cat on which reinstated the o2 sensor but just some extra info.
I’ve also compression tested the engine and it was 180psi across all 4 cylinders.
Car drives great just got that horrific idle.
Thank you for reading and i hope someone can help!
Sent from my iPhone using Tapatalk
I am having rough idle issues which I have been battling for a while now. Just off the bat here are the symptoms/codes/mods, I will follow with things I have tried to fix the issue. I know there are threads similar to this but none have solutions that have worked yet :/. So here goes:
Mods:
-sports cat
-ramair intake
Symptoms:
-idle misfires on cylinders 1 and 3 sometimes almost to the point of stalling but not very often
-plus fuel trims only at idle
-minus fuel trims when maf unplugged/runs better. Again only at idle.
Codes:
-P0133 02 Sensor Circ., Bank1-Sensor1:Slow Response (this code is normally no activity detected rather than slow response)
-P1103 Bank1-Sensor1, Heater Circuit
erformance Too Low-P1539 Clutch Pedal Switch: Implausible Signal
-it also has a brake module malfunction code which i can’t remember what it is exactly but can get that today if that would help. This doesn’t present a light on the dash though.
Now, you might say replace the o2 sensor however I have replaced it twice. There is a chance that it is the wiring however when looking at VCDS the sensor is working and trimming the fuel, it just shows a code that says it has low or no performance.
Anyway here are fixes that I have tried.
-replaced o2 sensor
-fixed all vac leaks including; deleting the SAI with blanking plate, rocker cover gasket, oil cap and a check valve which had split. The car was smoke tested to find these.
-new genuine bosch MAF sensor.
-4 brand new spark plugs.
The car runs better with the maf unplugged, and again you might say to replace maf but the maf sensor is reading within the specified limits and not malfunctioning. When unplugged the fuel trims go from +25 to -25.
I’ve also rearranged the ignition coils to see if the misfire moves with them but it doesn’t so not ignition coils.
The previous owner had the car mapped and had a straight pipe where the o2 sensor was removed entirely and the tuner 0’d the table of values for the o2 sensor to “delete it”. I’ve had that taken off and put a sports cat on which reinstated the o2 sensor but just some extra info.
I’ve also compression tested the engine and it was 180psi across all 4 cylinders.
Car drives great just got that horrific idle.
Thank you for reading and i hope someone can help!
Sent from my iPhone using Tapatalk
