My wife drives a 2004 2WD Explorer with the 4.0 SOHC motor. We have had a problem now for over a year and a half of it randomly dying. There is not telling when the engine might die besides the fact that it happens when you let off the accelerator to brake or make a turn. It only happens at slow speeds. At a stop light or stop sign usually. The car will always start right back up. It has been to a couple of Ford dealerships and they haven't been able to diagnose the problem. The check engine light is on and it is giving the code p0456. This code definition is an EVAP small leak detected. Probable causes for the code are 1. Defective, loose, or missing fuel cap. 2. EVAP Canister broke, hose cracked or not connected. 3. Purge or vent solenoid defective. 4. Vacuum leak at engine.

I don't think it's the fuel cap that would be making the car die. I used carburetor cleaner (I know its not the safest ) and sprayed on the vacuum lines that I could find to try and diagnose a vacuum line leak but nothing seemed to effect the engine. At this point I'll take any advice or recommendations about this issue. Do you think one of the other probable causes from p0456 could be causing the dying or could it be something else??? Any help is greatly appreciated.

 

Semi-wag: The 4.0 SOHC suffers from leaking intake o-rings. Some or all models have this issue. That would create a lean condition. Ford dealer should have checked that, as it's one of the first suspects. The evap system and fuel caps are pretty reliable. My '98 and '99 smoged perfect with original caps, the '99 passing in April of this year.

 

85e150six4mtod thanks for the heads up we will have to look in to that. Anyone else had similar problems or have any other ideas of what might be making our explorer do this?

 

If you clear the code, does that code reappear when it cuts off again? If not, that might be an issue, but not necessarily related to the shutdowns. While I've never had this happen on our two '02 Explorers, we had Aerostars for many years that would do this occasionally (but never threw a code). It was always in a turn or braking and was worse when the A/C was running too. The cause was a dirty idle air control valve (which wasn't hard to get to or expensive to replace)...not sure if the Explorers use that gadget or not. Good luck though...

 

Also check the age of the battery. If it is 3 years old or older, consider replacing it to see if that helps the situation.

My wife had a 2002 Lincoln LS that would randomly stall when sitting at a stop light, shifting from Reverse to Drive, etc. I tried several different things, then realized the common denominator was the brake pedal being pressed. One day I thought the vehicle sounded a bit labored when starting so I replaced the battery and never had another issue with the stalling. I suspect the extra load on the electrical system from having the brakes applied was dragging the system too low. The battery was only 3 years old at the time.

-Rod

 

Thanks for your answer. I have also read about the IAC possibly causing issues like this. However, I have also read some posts about the 04 explorer not having an IAC. Can anyone confirm or deny this claim? If it doesn't have an IAC what else could I try???

I have tried a new battery and a new alternator as well.

 

Looks like you made a separate thread about the IAC.

-Rod