Having too much boost is not always a good thing! Too much boost can increase
air flow and intake temperatures that can trigger dangerous detonation. You
would think more boost would be a good thing, but if you don't have enough fuel
to compensate for the increase in air flow and an intercooler that can keep intake
temperatures in check, it can lead to a dead motor.
Boost increase can be further subdivided into:
We'll concentrate on the first type - sudden and uncontrolled boost pressure
increase - first. This is something that happens all-of-a-sudden and can
usually be traced back to the operation of the wastegate. Usually, it's
a failure of a properly operating wastegate that allows the boost to increase
uncontrollably. First check the vacuum wastegate line from the turbo
compressor housing to the wastegate actuator. The hose can come loose
due to a bad hose or loose clamp. The fitting on the turbo compressor
housing can come loose or even pop off the turbo compressor housing itself.
The wastegate itself can fail due to a bad or torn internal diaphram, or the
actuator or flapper can seize. If the wastegate fails in the "closed"
position, you will run into a problem with runaway boost pressures!
- Uncontrolled and sudden increase in boost pressures
- Gradual increase in boost pressure also known as "boost creep"
"Boost creep" is a more subtle type of uncontrolled boost pressure increase.
Check out our boost creep page here:
FC3S Pro: Problems, Symptoms - Turbo, Boost Creep
For more information on detonation, please check out our Detonation page here:
FC3S Pro: FAQ - Detonation
Ensure any boost controllers are working properly!
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