neon won't run after warm up

Hey guys!

My buddy has been having a stroke of bad luck getting his neon going. His engine blew so he got a used one from the wreckers. The car runs and drives beautifully when it first starts, but after the engine warms up, the engine immediately dies and won't restart - before it dies it sounds like its running with a cylinder down. He has talked to technicians at dodge, and the shop he works at. He's replaced the coil, temp sending unit, air sensors, etc...pretty much everything! I don't know much about dodge engines but but the car doesn't seem to be able to make the transition from running cold, to running warm...Any suggestions? its a 95' model

Check the MAP sensor and I know on a bunch of 95's that had fuel pump issues that it would randomly stall when warmed up as the pump would overheat.

How long was the car sitting before he replaced the ebgine? The ecm could have an issue. The fuel pump is most likely, escpecially if it sat for a period of time. Do you have access to a scan tool, if so hook it up to the car check the codes. Look at the data as the car starts dieibg see if anything out of the ordinary.:2cents:

On my '98 the crankshaft position sensor would kill the engine after she was warmed up. The car would start and run for maybe five minutes and then die. I had to have the engine hot and dead and then immediately code her out or I got not data.

thanx fellas...I told him it sounded like a fuel pump but like I mentioned I don't know much about these cars. I think dodge told him to replace the map sensor and I'll mention the cam sensor and the fuel pump issue with these cars to him...

Thanx for all the input :)

Hey guys, I finally got some time to get to my buddies place and check this car out. As I mentioned before it dies after it warms up. But after listening to it myself I notice the idle starts going nuts before the engine shuts down. It idles like someone is in the car revving it up and down, but nobody is touching the gas at all. He tried swapping the fuel pump out with a junker and he said the engine runs longer before it acts up, which makes me question if the newer pump isn't defective to...what I'm wondering is: a post I read on here states you can make the computer do a self test by going - ACC/on/off/on/off/on within five seconds..is this a reliable test? the check engine light doesn't come on when I turn the key on, and I'm not sure if its supposed to. But nonetheless, the self test method didn't produce any codes for me

The CEL should come on when you turn the igntion to ACC-ON and then turn off after a few seconds. If it doesn't come at all, then it's possible the bulb burned out.

You should always get at least a code 55, which is end of codes.

When the engine dies, check to see if you still have spark going through the spark plug wires(final spark desination) when cranking the engine.




This will tell you if you have an ignition problem or a fuel delivery problem. I know it seems like a fuel delivery problem, but don't rule anything out.