What are the reasons for low turbo pressure?
4 Answers
The reasons for low turbo pressure are as follows: 1. Air filter: A clogged air filter in the turbocharger increases intake loss, resulting in insufficient boost pressure. Typically, the air filter should be thoroughly cleaned after 1500 to 3000 hours of use. 2. Excessive oil deposits in the air passage: If there are excessive oil deposits in the internal air passage of the compressor section, the airflow resistance increases when passing through the passage with more deposits, leading to a reduction in boost pressure. Regular maintenance should include periodic flushing of the turbocharger section. For medium and small turbochargers with internal support, the compressor housing can be removed for air passage flushing; for turbochargers with external support, which are more difficult to disassemble and clean, hydraulic flushing can be performed directly without disassembly, i.e., spraying water at the compressor inlet passage for cleaning. 3. Damaged air seal: For externally supported turbochargers, if the air seal on the back of the compressor is damaged, a large amount of air will leak from the back to the intermediate housing and be discharged along with the exhaust gas from the turbine, also causing a decrease in boost pressure. 4. Poor fuel combustion: Poor fuel combustion can lead to carbon deposits on the rotor section, or increased rotational resistance of the turbocharger due to bearing damage, both of which can result in a decrease in boost pressure.
The turbo pressure won't rise. As someone who's been repairing cars for 20 years, I think common issues include excessive wear of the turbocharger, seizure of the intermediate shaft or blades, which naturally prevents pressure buildup. Leaks in the intake pipe allow air to escape, so pressure definitely won't increase. A clogged exhaust system prevents exhaust gases from exiting, keeping the turbo speed low. It's also necessary to check the electronic control unit, such as faulty pressure sensors or vacuum valves, as inaccurate signals can cause the ECU to limit boost. A dirty or clogged air filter restricting airflow is another common cause. Inadequate daily maintenance leading to insufficient oil lubrication can cause the turbo to overheat and fail. When encountering such problems, first use a diagnostic tool to read the fault codes, then test the pipeline pressure, and troubleshoot step by step. Don't delay, as low pressure affects engine power and fuel consumption—safety comes first. Regular oil and filter changes are recommended to prevent major issues.
Last time my car's turbo pressure wouldn't go up, which was really frustrating. I suspect it's because I often drive at low speeds in the city, so the turbo doesn't fully activate, and accumulated carbon deposits clogged it up. If there's a slight leak in the intake pipe or connections, the pressure leaks out. Also, a clogged exhaust system, such as an aging catalytic converter, can obstruct airflow. If the air filter isn't replaced on time and gets dirty, it won't draw in enough air. Electronic components might also be the issue—faulty sensor signals could cause the system to limit pressure. Using low-quality fuel regularly leads to more deposits, making it easier for the turbo blades to get stuck. In such cases, you'll clearly feel the lack of power while driving, struggle when climbing hills, and notice increased fuel consumption. I tried checking the simple parts myself, but if that doesn't work, I'll take it to a repair shop to avoid damaging components due to improper handling. I recommend cleaning the filter every 10,000 kilometers to prevent small issues from becoming big problems.
My turbo car isn't building enough boost pressure. After checking, there might be several simple issues: the air filter is clogged and hasn't been cleaned or replaced in time. The intake pipe connection is loose causing air leaks, or the hose is old and cracked. The exhaust system is blocked, such as severe carbon buildup in the exhaust pipe or catalytic converter. The turbocharger itself has wear and tear, with blades not moving smoothly. There might be poor contact in fuses or wiring, affecting the control system. All these problems can lead to low boost pressure and weak acceleration when driving. When I was a beginner, I suffered losses by neglecting these small details. Now I understand that regular maintenance is key - don't let minor issues escalate into major repairs. It's safer and more reliable to have it checked at a professional shop.
