What are the reasons for insufficient turbocharged air supply in the Envision?
4 Answers
The reasons for insufficient turbocharged air supply in the Envision: 1. Leakage or detachment of the high-pressure intake pipe, the solution is to replace the high-pressure intake pipe; 2. If there is no change after replacing the high-pressure intake pipe, it is likely that the turbocharger is faulty, in which case the only option is to try replacing the turbocharger. The Envision is a mid-size SUV produced by SAIC-GM Buick, featuring a MacPherson strut front suspension and a multi-link rear suspension. In terms of body dimensions, the vehicle measures 4694mm in length, 1839mm in width, and 1686mm in height, with a wheelbase of 2750mm. For power, the vehicle is equipped with a 1.5T turbocharged engine, paired with a 7-speed dual-clutch transmission.
When repairing the Envision with insufficient turbo boost, the most common issue I found was air intake leaks. Those rubber hoses tend to age and crack after 5-6 years, especially near the high-temperature turbocharger area. Once I encountered a stuck wastegate valve causing insufficient turbo boost, making the car feel sluggish during acceleration. Sensor failures are also common - a dirty MAP sensor can mislead the ECU into reducing boost pressure. Of course, turbocharger itself failing is another cause, as bearing wear can prevent the impeller from spinning. If problems arise right after replacing the air filter, always check whether the airbox is properly sealed - these details are most easily overlooked.
Last time I drove, I encountered this issue - pressing the accelerator felt like stepping on cotton. Turned out the intercooler was completely clogged with willow catkins, cutting cooling efficiency in half. It's also quite common for the intake pipe joint sealing ring to age and leak air - just feel around the pipe connections for any hissing sounds. If the exhaust valve gets stuck in the normally open position, all the boost pressure leaks out. Poor fuel quality can also cause abnormal exhaust backpressure, indirectly affecting turbo performance. These hidden problems often don't show up when reading OBD trouble codes - you need to actually measure the boost pipe pressure to diagnose them.
I think these key points should be noted: When carbon deposits cause turbine blade sticking, the RPM won't increase - just like how my car improved after turbo cleaning; If the intercooler's cooling fins get clogged with mud, it affects intake air density; Oil contamination interfering with the MAF sensor will cause low readings; The most troublesome issue is ECU programming problems - last time it was only resolved after flashing new firmware. Of course, basic maintenance shouldn't be neglected: replace the air filter every 20,000 km and check turbo shaft clearance every 50,000 km.
