2003 Ford Explorer has idle issues and check engine light on?

[struckanerve]

Our 03 Explorers check engine light came on about a month ago. We took it in and the mechanic said it was the upstream o2 censors. Since then the idle has become worse and worse until it finally started dying at stop lights. We went to Autozone to pick up the censors and they pluged into our computer and the read out said the master air censor was also bad. They said that we should go down the list of things that could be causing the problem. The first was replace the fuel filter, since we had owned the car for 6 months and it had never been replaced, as well as add some fuel treatment. We did that, didn't fix the problem. Check engine light is still on and idle is still horrible. So our mechanic friend was checking things out. When he unpluged the master air censor the idle problem went away, pluged it back in and the truck dies. So we went and bought a new censor, same problem with the new one.
The truck doesn't die right away or have the idle issues until it's been running for a while. Usually it takes about 20 minutes for it to start running pretty rough and then want to die at stop lights. When it starts it seems to have surges in the gas flow, and then cut out, this goes on for a while until the truck cuts out completely. Would the o2 censors cause this? What else could be the problem? We're about out of ideas, and nearly out of money. We would greatly appreciate any help.

 

[Bruce]

Being that you have replaced the O2 sensor with a "New" one the O2 sensor is not the problem. Your SUV is new enough that most people don't ever have problems with the fuel filter because it is still relatively new. Sorry, to me an 03 is still kind of new. lol besides my bias I don't think you need to replace that filter unless 70% of the times you pumped fuel into the vehicle there was a Tanker pumping Fresh fuel into the ground. (this would move sediment around and make it convey into your tank=bad...) If my scenario is not true, I belive you should check the Ignition system. Certain Parts as follows: Distributor Cap, Rotator Cap and, Catching Coil. I also Suggest that you have your timing set before you have a mechanic begin to check the parts I listed. The reason Why I feel that your distributor cap may be the problem is because of a problem I had with my 93' Chevrolet S-10. Dispite the difference in age, a decade, both of these vehicles are ignited the same way plus or minus a few perks and computerized systems. My Thesis is that Your Distributor Cap, is not making direct contact with the rotator button of which is immedeately under the distributor cap and over the Catching Coil. I had this problem with my truck and it had similar problems I can describe as: Shaky, choking, jumpy, or un-even acceleration and the lack of Idle (turning off at stops without extra gas).

When it comes to suddenly getting a wild boost when carefully adding "pedal" to your acceleration I also Suggest that you replace your Throttle Body Position Sensor of which on most engines (excluding Supercharged, and Turbine assisted engines) is on the side of the opening where the ribbed rubber hose ends and meet the metal intake.

If you dont understand some parts of what I have explained be sure to have your friend who is a Mechanic read over my answer. Though I am no mechanic my self I feel it would be better interperteded that way. I mean no insult to anyone in saying that...

Good luck. I hope my insight helps you with fixing your Explorer.

My E-Mail is open for any further questions.

 

[kmp1171]

I can definitely help but to be more accurate do you remeber the codes what were the code #'s and what engine is in this veh let me know quick and i will get right back to you [email protected] I do not mean to sound rude but the answer you got from the guy think bruce is name is incorrect . and i am not trying to get u to buy anything.

 

[NixonBackAgain]

Check the idle air valve. If it struggles to keep going when idling or stalls when braking/in low gear then this is a high probable cause.

The idle valve regulates the flow of air & fuel. They get clogged up in older cars and can stick causing idle problems. Not sure where it is on a Ford Explorer but they are the sort of thing you can change yourself and can be had off ebay pretty cheap.

Removing your one and cleaning it out with a spray of carb cleaner may help.