280 sel 4.5 wont start when hot.

[awarne]

I replaced some water sensor that the guy said would fix it, but
it didnt. The other wierd looking thing he said would fix it looks like it has already been replaced and there was an old one in
the trunk. He said that was good cuz there 100 something dollars
anyways. I was thinking fuel pump.
please help! thanks

[Clunker]

The 4.5 can vapor lock. What do you mean by hot? Is the engine overheating?

[awarne]

It starts fine when it is totally cold, when warmed up if I turn it
off then start it again, it starts fine. but the longer it sits then the harder it is to start. Another thing is I replaced the fuel filter and when I was finished the fuel line from the pump to the tank was leaking Could this be the problem. maybe the loss of pressure.

Thanks for the help

[bill4247]

I have the same car with the same problem (see my most recent post and responses). I tried a can of Syntec injection cleaner and it helped alot although still not perfect. I have come to the conclusion that one or more injectors leak for a while after I shut down resulting in flooding of the combusion chamber(s) not starvation due to vapor lock. But I could be wrong. The reason I think the syntec helped is because it removed some gum allowing the injectors to more properly close when the engine is shut down. The definitive test would be to pull the plugs after you shut down to check for wetness.

[awarne]

problem fixed, there is a check valve on the fuel pump that holds
pressure, I also noticed all my fuel hoses were worn out and one was leaking slightly. if you have the same problem you should try
spraying starting fluid in the intake to make sure that it is a flooding problem rather than a lack of fuel like mine. if it responds to the starting fluid then its not your injectors. there is also like I said earlier a 150$ part that is usually the problem or else a water sensor.