<Table> <Tr> <Td> </Td> <Td> This article does not cite any sources . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (February 2007) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article does not cite any sources . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (February 2007) (Learn how and when to remove this template message) </Td> </Tr> <P> A flooded engine is an internal combustion engine that has been fed an excessively rich air - fuel mixture that cannot be ignited . This is caused by the mixture exceeding the upper explosive limit for the particular fuel . An engine in this condition will not start until the excessively rich mixture has been cleared . It is also possible for an engine to stall from a running state due to this condition . </P> <P> Engine flooding was a common problem with carbureted cars, but newer fuel - injected ones are immune to the problem when operating within normal tolerances . Flooding usually occurs during starting, especially under cold conditions or because the accelerator has been pumped . It can also occur during hot starting; high temperatures may cause fuel in the carburetor float chamber to evaporate into the inlet manifold, causing the air / fuel mixture to exceed the upper explosive limit . High temperature fuel may also result in a vapor lock, which is unrelated to flooding but has a similar symptom . </P>

What does it mean when you flood your engine