96 Explorer sputtering issues

[Shoshanna]

I bought a used 96 Ford Explorer XLT last year in the arid Okanogan highlands of Eastern Wa. and so this is my first summer driving it here. The check engine light has been on and I was told by a b-rated mechanic that it wasn't urgent, but that the entire fuel system needed cleaning, so I've been putting off doing anything until I got more funds.
We recently had 120-degree weather here and the engine was sputtering and nearly stalling so I am working on the issue with the local Chevy dealer/service nearby. They replaced the Heated Oxygen Sensor (HO2S) Bank 1 Sensor 1 today and it runs smoother but the mechanic says its still running rough and needs an upstream O2 sensor(right)(B2S1), so I will have that replaced next week. It is still sputtering at around 40mph, but I don't drive it at top speed much which mechanic told me I need to do more of. I live in a small town and so I guess I've babied it a little. It also needs a ball joint and I have also waited on funds to fix that but now that I know the sensors were the main issue I've focused on that for now.
Are there any suggestions as to the new diagnostic codes? P0133, P0153, P0420.
He seems to imply there may be more involved if the next sensor doesn't stop the sputtering, but he wasn't real clear.
I'd like a second opinion at this point.
Thank you for any recommendations,
Shoshanna

 

[DemonMudder]

Well, I had a friend at work that had the P0420 code on her Scion XB, in her case it was the O2 sensors. I haven't personally ever seen P0133 or P0153, but front what I can find they are both the O2 sensors as well. So, give those a shot first and let us know how that goes. As for the babying it thing...that I'm not sure on believing, I'm not usually on too much highway with my '99 Explorer, usually max at out 55 mph going anywhere and it hasn't affected mine. I prefer backroads so even 55 mph is pushing limits.

 

[EB4X]

Sounds just like yours:

https://www.justanswer.com/ford/1i8wn-1996-explorer-codes-p0153-p0420-p0133.html

The connector harnesses (on some) are not the easiest things to get to ...but if you could have someone unplug the other O2 sensors the PCM will go into a default set of parameters not being able to read the unplugged sensors and thus should run much better - confirming issue is the sensors.... and giving you a better running vehicle until you get back / around to replacing them.

 

[XLTrunner]

I don't understand the "entire fuel system needs cleaning" comment from your first mechanic. Did the truck sit unused for a long period of time and the gas became stale? I'd change the fuel filter (probably needs it anyway as part of regular maintenance) and throw a can of Seafoam gas treatment in the tank to see if that helps.

 

[Shoshanna]

Sounds just like yours:

https://www.justanswer.com/ford/1i8wn-1996-explorer-codes-p0153-p0420-p0133.html

The connector harnesses (on some) are not the easiest things to get to ...but if you could have someone unplug the other O2 sensors the PCM will go into a default set of parameters not being able to read the unplugged sensors and thus should run much better - confirming issue is the sensors.... and giving you a better running vehicle until you get back / around to replacing them.

not too sure if he knew to unplug the other sensors before replacing the heated oxygen sensor today, but they called Ford about Powertrain Control Module software to reflash for codes PO100, PO153(according to fix summary, tech tips)because she said that Ford needed to do that, which I didn't quite understand. She then said they would simply need to replace the upstream O2 sensor next. The mechanic wasn't certain this would fix the sputtering problem. Check engine light is out now, but he said he got the codes mentioned in my first post.
Are you saying that the sensors should remain unplugged if they are bad? Chevy said they would just be starting with these two new sensors, but wasn't sure it would fix the sputter. They will probably continue to recommend replacing other sensors until the sputter is fixed. They don't seem to have any other ideas at this point.

 

[Shoshanna]

I don't understand the "entire fuel system needs cleaning" comment from your first mechanic. Did the truck sit unused for a long period of time and the gas became stale? I'd change the fuel filter (probably needs it anyway as part of regular maintenance) and throw a can of Seafoam gas treatment in the tank to see if that helps.

the first mechanic does not come highly recommended by anyone and Chevy doesn't understand why he's still in business at all they hear so many complaints about them. He wasted a lot of my time and money and I'm not the first to say that. The fuel filter is still clean and I have used gas cleaner as well as fuel injector cleaner recently.

 

[Shoshanna]

Well, I had a friend at work that had the P0420 code on her Scion XB, in her case it was the O2 sensors. I haven't personally ever seen P0133 or P0153, but front what I can find they are both the O2 sensors as well. So, give those a shot first and let us know how that goes. As for the babying it thing...that I'm not sure on believing, I'm not usually on too much highway with my '99 Explorer, usually max at out 55 mph going anywhere and it hasn't affected mine. I prefer backroads so even 55 mph is pushing limits.

This Explorer has had a check engine light on for a year without proper diagnosis, which I just got from Chevy this past week. I was given some bad advice and waited to do anything till now, so I have babied it in the condition it's in cuz I live in a small town anyway, but I'd like to get it out on the back roads where I live this summer somehow. I've done 60 and even 70 on the hywy and it's been ok until this sputtering started recently with the hot weather. This is 4x4 country with a lot of primitive roads so this vehicle needs to be in good shape to take it out where I'd like to go.

 

[Mbrooks420]

Check the fuel pressure.

 

[96eb96]

the first mechanic does not come highly recommended by anyone and Chevy doesn't understand why he's still in business at all they hear so many complaints about them. He wasted a lot of my time and money and I'm not the first to say that. The fuel filter is still clean and I have used gas cleaner as well as fuel injector cleaner recently.

There are many things that can cause these symptoms, and they have to be diagnosed correctly. The 96 overall is very reliable but there could be one kind of major thing (cracked heads) that can cause issues. There is an inexpensive solution too that often works.


Google MAF Cleaning, try that first. You really need a scan tool and some knowledge to pin it down. Usually P0133 means slow o2 sensor response, so changing the o2 sensor MAY fix the problem. But being on BOTH sides, makes it a bit suspicious. A dirty MAF could create the same effect (or maybe not). If that is the case, you can replace all the o2 sensors and still have issues.

Codes NEVER tell you something is bad. Rather that some parameter isn't meeting spec. The analogy is the temperature in your fridge goes up. It could mean the fridge is broke or someone left the door ajar. Both give the same codes.