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Flooded fuel-injected engine?

How is it possible that a fuel injected engine floods? I thought only a carbureted engine does that. I couldn’t start my car–battery wasn’t dead–but wouldn’t turn over. Tow truck driver told me it was flooded; told me what to do (i.e. hold gas down part-way etc.) and it worked. lots of smoke came out of exhaust but then ran fine.

I’m not sure how it happens, but I’ve seen two different cars of different makes do just the same thing in the last couple of years. One is a 1999 Infinity G20. The other was a 2003 Honda Accord. Both solved with the same method, and as of yet, no recurrence of the flooded condition. Just weird. I recognized the symptoms, but cannot tell you how it happened.

It’s not common for a fuel injected vehicle to flood but they certainly can. If injectors stick open or there is high fuel pressure then the engine will flood. The fuel pressure that normally remains in the system can drain out through the injectors and cause the flooding condition. I would recommend that you have the Jag checked out by a good mechanic.

In a properly operating system you won’t see a flood. Now if an injector spray pattern is poor and no fuel atomization occours you could get a flood, or if plugs are worn or oil fouled you could get a flood or if the backside of the valve has deposits and prevents the fuel air mmixture from entering the chamber intact, you could get a flood. You see the flood condition is an indication of a problem up the line somewhere.

Injectors can leak… I bought a bargain set of injectors for a V8 Caddy on e-Bay for $140, brand new…They indeed cured a nasty random misfire problem and I was elated at my genius. But ever since, that instant start at the turn of the key was gone…I learned to hold the throttle open on a hot start. The bargain injectors were seconds, rejects off the test bench and they all drip a little after engine shut-down…

Sometimes CLEANING formerly sound injectors will cure this. Techron or BG-44 work…

I think Oldschool hit on something. Carbed engines could flood because of the drivers rather than the fuel systems.

A properly functioning carburated engine could be flooded out because they ran rich anyway and repeated pumping of the gas pedal could empty the float bowl into the intake flooding the engine. A properly operating fuel injected car is not subject to the same driver error. They run lean to begin with and you can pump the pedal until your foot falls off without pumping excess gas into the instream.

In addition to leaky injectors there is the fuel pressure regulator most (all?) of which work off of engine vacuum. When its diaphragm fails the vacuum is sucking fuel into the intake. This can cause or contribute to a no start when the car has been run and then shut off for a while, and lead to rough, smoky running.