DeVille V8-4.6L VIN Y (1998)
Fuel: Description and Operation
Fuel System Deposits
FUEL SYSTEM DEPOSITS
Fuel system deposits can cause various driveability problems. Deposits usually occur during hot soaks after key 'OFF.' Poor fuel quality or driving
patterns such as short trips followed by long 'cool down' periods can cause injector deposits. This occurs when the fuel remaining in the injector tip
evaporates and leaves deposits. Leaking injectors can increase injector deposits. Deposits on fuel injectors affect their spray pattern, which in turn
could cause reduced power, unstable idle, hard starts and poor fuel economy.
Intake valve deposits can also be related to fuel quality. While most fuels contain deposit inhibitors, some do not and the effectiveness of deposit
inhibitors varies by manufacturer. If intake valve deposits occur, fuel may be suspected. These deposits can cause symptoms such as excessive
exhaust emissions, power loss and poor fuel economy.