Mysterious Optra Magnum engine problem - 12k km

kj302 · 20th February 2014, 20:14

I own a Aug 2008 Model magnum diesel, which has done around 1.17 lakhs km. Since 2010, car is experiencing a strange problem. After driving at 120+ speed for 15-20 mins (especially on a hot afternoon), the car goes to limp mode, power drops, speed slowly drops to 100 kmph and engine check light comes on. Pedal position, gear change has no effect on the power. Need to restart the car to get the power back, only to be repeated in half an hour.

The car has gone through few modifications, tuning box (from petes) later replaced with a ECU remap(from TDI Racing) and a green cotton storm filter, which got later replaced with a stock filter. But I dont think the problem has been caused by these mods.

Service centers (tried with three of them) had no clue and every time they just reset the code. So i decided to get my hands dirty and procured a OBD2 blutooth adapter. Figured out the fault code from ECU

Fault code : p0299 (Turbocharger/Supercharger "A" Underboost Condition)
This link has more details. http://www.obd-codes.com/p0299.
It essentially points to issue with Turbo.

The following are the fault reports and freeze frames. (I assume freeze frame are the instantaneous sensor reading at the time the issue occurred)

Current Fault Log
------------------
P0299: Unknown code - More information may be available on the web
Pending Fault Log
------------------
ECU reports no pending faults
Historic Fault Log
------------------
ECU reports no historic faults
Other discovered fault codes
(possibly pending, current or manufacturer specific)
----------------------------------------------------
ECU reports no other fault codes logged

Freeze frame information:
------------------
Engine Load = 75.686 %
Engine Coolant Temperature = 83 °C
Intake Manifold Pressure = 27.412 psi
Engine RPM = 3,289 rpm
Speed (OBD) = 144 km/h
Intake Air Temperature = 16 °C
Mass Air Flow Rate = 99.77 g/s
Fuel Rail Pressure = 22,177.721 psi
Distance travelled since codes cleared = 5,120 km
Barometric pressure (from vehicle) = 13.343 psi
Voltage (Control Module) = 14.115 V
Accelerator PedalPosition D = 65.882 %

TBHP experts could help me in deciphering more from these data? If I a can pinpoint the fault, then I could tell the service center folks exactly that and direct them, as they were totally clue less all these time.

20th February 2014, 20:14	#46
kj302 BHPian Join Date: Dec 2007 Location: Bangalore Posts: 39 Thanked: 5 Times	Optra Magnum - limp mode with engine check light on I own a Aug 2008 Model magnum diesel, which has done around 1.17 lakhs km. Since 2010, car is experiencing a strange problem. After driving at 120+ speed for 15-20 mins (especially on a hot afternoon), the car goes to limp mode, power drops, speed slowly drops to 100 kmph and engine check light comes on. Pedal position, gear change has no effect on the power. Need to restart the car to get the power back, only to be repeated in half an hour. The car has gone through few modifications, tuning box (from petes) later replaced with a ECU remap(from TDI Racing) and a green cotton storm filter, which got later replaced with a stock filter. But I dont think the problem has been caused by these mods. Service centers (tried with three of them) had no clue and every time they just reset the code. So i decided to get my hands dirty and procured a OBD2 blutooth adapter. Figured out the fault code from ECU Fault code : p0299 (Turbocharger/Supercharger "A" Underboost Condition) This link has more details. http://www.obd-codes.com/p0299. It essentially points to issue with Turbo. The following are the fault reports and freeze frames. (I assume freeze frame are the instantaneous sensor reading at the time the issue occurred) Current Fault Log ------------------ P0299: Unknown code - More information may be available on the web Pending Fault Log ------------------ ECU reports no pending faults Historic Fault Log ------------------ ECU reports no historic faults Other discovered fault codes (possibly pending, current or manufacturer specific) ---------------------------------------------------- ECU reports no other fault codes logged Freeze frame information: ------------------ Engine Load = 75.686 % Engine Coolant Temperature = 83 °C Intake Manifold Pressure = 27.412 psi Engine RPM = 3,289 rpm Speed (OBD) = 144 km/h Intake Air Temperature = 16 °C Mass Air Flow Rate = 99.77 g/s Fuel Rail Pressure = 22,177.721 psi Distance travelled since codes cleared = 5,120 km Barometric pressure (from vehicle) = 13.343 psi Voltage (Control Module) = 14.115 V Accelerator PedalPosition D = 65.882 % TBHP experts could help me in deciphering more from these data? If I a can pinpoint the fault, then I could tell the service center folks exactly that and direct them, as they were totally clue less all these time.
	() Thanks