So my car seems to have developed a problem where wgdc starts to oscillate and boost drops by around 1psi at higher rpm when hot. The problem disappears after a few hours of cool down. Has anyone experienced anything similar?
My mechanic suspects the turbo vacuum actuators which may leak when the turbos are hot only. Not sure if this is possible? I also guess it is hard to properly leak test them cold vs hot? @Chris@VargasTurboTech
I have divided into hot and cold logs below. Each pair of logs were done with identical hardware and fuel. No adaptations reset in between.
When I write hot below, it means the car has been driving at normal operating temps for a good amount of time. By cold I mean the engine has just finished warming up, and the oil temp needle has started to move. Transmission and other auxiliaries may not be super warm yet. So a typical cold scenario is where the car has idled in the workshop for a few minutes, and then driven to the test strip around 10mins away from the shop. A typical "hot" scenario would be where the car has been driven for at least one hour, and where the turbos have already been exercised a bit on the way.
Logs posted below.
Here's an overview of mods on the car. Boost solenoids are less than one year old. So are vacuum lines. Brake booster is 10 years old and may be leaking a tiny bit; Brake pedal sometimes goes stiff after parking for a few hours.
My mechanic suspects the turbo vacuum actuators which may leak when the turbos are hot only. Not sure if this is possible? I also guess it is hard to properly leak test them cold vs hot? @Chris@VargasTurboTech
I have divided into hot and cold logs below. Each pair of logs were done with identical hardware and fuel. No adaptations reset in between.
When I write hot below, it means the car has been driving at normal operating temps for a good amount of time. By cold I mean the engine has just finished warming up, and the oil temp needle has started to move. Transmission and other auxiliaries may not be super warm yet. So a typical cold scenario is where the car has idled in the workshop for a few minutes, and then driven to the test strip around 10mins away from the shop. A typical "hot" scenario would be where the car has been driven for at least one hour, and where the turbos have already been exercised a bit on the way.
Logs posted below.
Here's an overview of mods on the car. Boost solenoids are less than one year old. So are vacuum lines. Brake booster is 10 years old and may be leaking a tiny bit; Brake pedal sometimes goes stiff after parking for a few hours.
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