P0299 issue solved
08-10-2019, 05:45 PM
#1
New Member
Thread Starter
Join Date: 02-11-2013
Location: Germany
Posts: 29
P0299 issue solved
Hi at all,
I had a P0299 problem that I could solve.
P0299 means underboost, error code is set if the turbo target pressure was not reached after 4 seconds.
symptoms:
- Only 6 - 10 psi, after further insistence on the gas the diagnostic light comes on and the pressure drops to 0 psi
- In my case, full turbo pressure in cold weather (10-12°C), 20-24 psi (tuned), after prolonged driving and accelerating the total failure, 0 psi.
- In very hot weather, about 38 °C, about 10 psi, after accelerating 4 seconds 0 psi.
Troubleshooting:
- Since I had full pressure in cold weather, I assumed that the pipes and intercooler are all right, no leaks or cracks.
- Vacuum hoses and connections checked, all right.
- Bypass valve is stuck? Remove air filter, then I can get better reach this, the Forge bypass valve is stiff, the fat had absorbed dust and was like glue.
Piston and cylinder cleaned, greased and reinstalled. Those who have the original bypass should check the membrane for perforation.
- Wastegate spring is fine, the linkage is firmly attached, so the wastegate flap is closed.
- Two solenoids, one for the wastegate, the other for the bypass valve. When power on, the solenoid must audibly "clack".
In my case, the solenoid for the bypass did not click. The ohmmeter on the connections shows no resistance.
Function of the solenoid for the bypass: to the solenoid is pressure from the pressure pipe to and negative pressure (via vacuum tank)
from the intake manifold. The output of the solenoid goes to the bypass valve.
- With 12V power, the pressure path is open, the bypass valve is closed, the boost pressure can be built.
- 0V (or faulty), the bypass valve is open, the charge pressure is recirculated, no boost pressure.
>> Link to bypass valve solenoid picture <<, thanks to firemangeorge
Why the failure of the solenoid in warm weather or only after a long journey: the solenoid expands when heat,
a break in the wire coil interrupts the circuit. Cold, the coil is contracted and can work for a short time.
Maybe this contribution helps one or the other with troubleshooting.
Greetings, Yves.
I had a P0299 problem that I could solve.
P0299 means underboost, error code is set if the turbo target pressure was not reached after 4 seconds.
symptoms:
- Only 6 - 10 psi, after further insistence on the gas the diagnostic light comes on and the pressure drops to 0 psi
- In my case, full turbo pressure in cold weather (10-12°C), 20-24 psi (tuned), after prolonged driving and accelerating the total failure, 0 psi.
- In very hot weather, about 38 °C, about 10 psi, after accelerating 4 seconds 0 psi.
Troubleshooting:
- Since I had full pressure in cold weather, I assumed that the pipes and intercooler are all right, no leaks or cracks.
- Vacuum hoses and connections checked, all right.
- Bypass valve is stuck? Remove air filter, then I can get better reach this, the Forge bypass valve is stiff, the fat had absorbed dust and was like glue.
Piston and cylinder cleaned, greased and reinstalled. Those who have the original bypass should check the membrane for perforation.
- Wastegate spring is fine, the linkage is firmly attached, so the wastegate flap is closed.
- Two solenoids, one for the wastegate, the other for the bypass valve. When power on, the solenoid must audibly "clack".
In my case, the solenoid for the bypass did not click. The ohmmeter on the connections shows no resistance.
Function of the solenoid for the bypass: to the solenoid is pressure from the pressure pipe to and negative pressure (via vacuum tank)
from the intake manifold. The output of the solenoid goes to the bypass valve.
- With 12V power, the pressure path is open, the bypass valve is closed, the boost pressure can be built.
- 0V (or faulty), the bypass valve is open, the charge pressure is recirculated, no boost pressure.
>> Link to bypass valve solenoid picture <<, thanks to firemangeorge
Why the failure of the solenoid in warm weather or only after a long journey: the solenoid expands when heat,
a break in the wire coil interrupts the circuit. Cold, the coil is contracted and can work for a short time.
Maybe this contribution helps one or the other with troubleshooting.
Greetings, Yves.
Thread
Thread Starter
Forum
Replies
Last Post
ATLsilverSS
SS Specific Service Issues/Repairs
15
11-11-2014 05:17 PM