1993 XLT Fuel Pressure Regulator/EGO not switching code72, and the check engine light

[RadioFlyer91]

I have been researching a problem that occured on my fathers 1993 Ford Explorer (98,000miles). It seems that there are many members who have made this repair before. I would like to get a common list of those who have had this problem and used the following solution.

The symptom. My fathers explorer seems underpowered as compared to my 1991 Explorer XLT. The 93 also uses more fuel than my 91 on trips. The 93 will stall when shifting from park into gear after sitting over night in the Virginia Climate, hasn't here in Tennessee. Furthermore, the 1993's check engine light will come on after a period of driving interstate underload. This has only occured when the vehicle was driven on the interstate for a period of time, not any other time. Teh vehicle has never been driven interstate since purchased except the 2 times when the fault occured. The 1993 has gas contamination in the crankcase (common sympton of a sticking or faulty Fuel Pressure Regulator.)

The code. I forget exactly the code number, believe it was 72. The code I pulled after the trip was EGO not switching. This is the right side EGO, the vehicle has 2 EGO sensors.

The Dilemma. I am not in a position where I can spend money to solve two problems. Trying to get it right the first time. The repair I make can't be effectively tested without at least a 1 hour road trip.

My educated guess. Currently my plan is to replace the Fuel Pressure Regulator and change the oil to get the contaminated out. I believe this will solve all problems, and since the O2 sensor appears to be working properly during in town driving and on the scan tool. I will then only replace the O2 sensor if the code reoccurs during the trip.

Thanks to many posters, especially Ira I have made this synopsis.

Whom ever has had this problem and found a successful fix for it, and if you don't mind, please post your fix. From what I understand from the dealer, the Fuel Pressure Regulator is generally the problem.

Thanks for the help in this matter. Look forward to having the vehicle back to 100 percent.

P.S. I was offerend 12 grand the other day for my 1991 because it is one of the explorers built in 1990. What a concept huh?

Thanks again.

 

[Grateful11]

Sounds like the exact problem I fixed over the weekend. It only takes about an hour to change the FPR. Mine was doing the exact same thing on the interstate but doing it daily. I'm sending you a link to a page with complete directions and they fit the situation to a tea. Follow them and you won't have a problem. I ended up cleaning my O2 sensor instead of replacing it. Only took a few minutes. As soon as I fill the tank back up I'm going to post the results of the minor surgery I did last weekend. Mine went from 23.6mpg to 13, can't stand that, hopefully it will be back up. It's looking good so far.

Dead Link Removed

Good Luck

 

[Triton46]

What tool did you use to see if your O2 sensor is working? I changed out my FPR and O2 sensor about a month ago, had the same problem you did. Check engine light came on, on the highway and would remain on.

The problem went away for a few weeks but now the light came on then went off leaving a code 41 (No heated O2 sensor). Very odd, but I won't know for sure until I take a highway trip.

Replacing the FPR has brought my mileage backup and power has been about the same.

 

[SteveVB]

Who offered you 12k for a 90 explorer, My Navajo was built 10/90, the engine is dated 8/90, and it was delivered 11/8/90. First Navajo off the lot to a paying customer. So send them my way. Ill sell it and buy two more!!

 

[Ira]

Triton46,

Check out my previous post from back in January. http://www.explorerforum.com/forums/showthread.php?threadid=14637 If you read on down a little ways, I gave the specific method I used to diagnose the O2 sensor. The only problem is that you have to make a test harness if you want to try this. Also, keep in mind that all this was done prior to my finding out the Fuel Pressure Regulator was sticking. Since I replaced my FPR back around Feb of this year, I have not had a single check engine light to come on...knock on wood.

RadioFlyer91,

From what I remember, my Explorer was also built in October of 1990. I will sell for 12 Grand...send them my way too.

 

[Grateful11]

Reply: What tool did you use to see if your O2 sensor is working?

I didn't check my 02 Sensor. I'm just going on a hunch from what I've read here that it was purely the FPR and not the 02 Sensor. Even though the test that was run said it was bad. I cleaned it with electrical cleaner and a soft clean rag. So far it looks good, no check engine light yet.