Need Help! Intermittant no start.

[extsp2]

Please help guys. I have a 2006 with a 4.0 that has a no start/no fuel every couple days, more so after sitting for a while like overnight. When it does start I can hear the fuel pump when turning the key to run before starting. When it doesn't start I do not hear the pump. If I spray a touch of starting fluid in the throttle body it starts right up and will run and start all day. It seems like a sensor or something is telling the PCM it's not ready for fuel but after that initial start it's fine for a few days. I need to figure this out, it's the wife's car.

 

[Flag Gibby]

Sounds like a low fuel pressure causing the system to leak down/cutout. I would start by resetting the fuel inertia switch, changing the fuel filter if it has been longer than 30k miles since the last change and then checking the fuel pressure to verify that it is in spec. If the fuel pressure is low after doing everything else then the fuel pump is bad and needs to be replaced.

 

[extsp2]

Could any of that cause the pump no to pump on crank? When it's going to start I can hear the pump, when I don't hear the pump is when it won't start, but a quick shot of ether and it starts and is fine all day or for a week. I borrowed a friends Scanner and was able to get the pump to work on command every time. At that time the psi was in spec. Could a fuel pressure sensor or FPDM cause this?

 

[Flag Gibby]

That to me would be either the fuel inertia cutout switch or the PATS system kicking in and killing the fuel pump. Although, you being able to get it to start with ether and the fuel pump having good pressure makes me wonder if you clean the MAF sensor and the throttle body if your problem will go away.

 

[Flag Gibby]

Was reading around and should have mentioned for you to check your battery and charging system as well as those connections. A weak battery/bad connections can cause unusual issues and you do mention that it likes to do it after the vehicle sits overnight.

 

[extsp2]

Battery is good and connections are nice and clean and alternator is good. I will clean the MAF and throttle body. Thanks for the ideas, I had some thoughts but need other people's ideas too.

 

[MotorCityFats13]

pats on a 4th gen causes a no crank condition.... you get the same thing if you disconnect the cluster, so I would rule that out