97 Ford Explorer 5.0 Cold Startup Idling and stalling problems.

[RoCkrMAN]

Hello there, I am new to this and I have searched EVERYWHERE & EVERYTHING! I can not seem to get a solid answer for this. Every time my explorer cools off and I start it up it goes to about 1500 rpms then drops to 500, then to 400, so on till it dies. If I put it in drive and drive it while its doing this it backfires and has no power. Seems like a pooping noise coming from under the hood. I can put it on down and it barely goes. It is a real pain since I can't let it warm up in the mornings now it does stop after 3-7 mins. CEL says this P0141, P0171, P0174,P0171pd, P0174pd. I just changed the upper intake today and it still does the same thing. Also some days if i put it down it seems like you can feel more power come threw. Not sure if that is the computer Mixing itself but Some days it runs like a champ and some days it feels like I have a banger under the hood. If anyone could help me solve this it would be so appreciated! Hope you have a nice day!

 

[Thugology101]

I would be wondering about your fuel rail pressure sensor. If its bad your fuel pressure could be low. However "heater circuit" is the only O2 code that is definitely a sensor problem. All the other O2 codes are symptoms. A heater circuit code means the sensor is bad, the wiring is damaged, or there's a signal problem to the wiring.

 

[Thugology101]

It would also help to know if its stock or if changes have been made. Intake changes, exhaust changes, flashes, etc.

 

[RoCkrMAN]

It has a true dual flowmaster exhaust and the back two cats are gone. It has a cheap filter just not the whole thing. That's all that has been done. Could the temp sensor have something to do with it?
It also is getting very bad gas mileage. (Full tank gets bout 150miles) and as far as the o2 sensor that code only comes up every now and then. Also could the egr have anything to do with it?

 

[RoCkrMAN]

Well after changing upper intake, temp sensor, air change sensor, and MAF it runs like a new one again. Im pretty sure it was the MAF. Thanks for your help!