I think it's a misfire... help please

[allsounds]

I have an '03 XLT V6, with 58K miles on it. I just got it a little over a month ago. It started running a little rough about 3 weeks ago, but very intermittently. The SES light came on though, and that bothered me. So I took it to autozone, and they told me that bank one sensor one was bad (o2). So I bought the sensor, and had a local shop install it. He calls me and tells me that 2 sensors are actually bad so he replaces the other bad one too. He clears the code and off I go. 3 blocks later the SES light pops up again , I bring it back, same code bank one sensor one. He clears it and I'm off again. I took the truck home and parked it, still no light. 2 hours later I go to run to Target, press the auto start on the explorer, go out and sure enough... my friend "light" has popped on again.

OK... SYMPTOMS:

1. When shifting from reverse to drive sometimes the RPMS drop way low like it is about to die, but then goes back up to normal.

2. Some times at lights when I come to a stop the car RPMS drop down low but go back to normal again.

Sorry for the long post, I am trying to be very detailed. Thanks in advance.

 

[Donner]

Have you changed or had changed the fuel filter recently? What type of gas brand do you use? I don't know anything about the SES light.

 

[allsounds]

Have you changed or had changed the fuel filter recently? What type of gas brand do you use? I don't know anything about the SES light.

When I brought the car in this weekend the mechanic told me that there was a tune up done on the vehicle recently, and he also said it should have not been needed to be done because it only had 58k miles on it.

 

[Donner]

Fuel filters are changed about every 25-30k. Unless it was changed during the tune up, you should have that changed. How about that gas, what brand do you use?

 

[allsounds]

Fuel filters are changed about every 25-30k. Unless it was changed during the tune up, you should have that changed. How about that gas, what brand do you use?

usually i put regular in, every 4th fill up I put premium in... It is on a tank of premium right now.

 

[Donner]

Fuels with additives work best... Chevron, Texaco, BP, or you can add your own bottle if you're not using a detergent. There are other things that could be causing this hesitation also. We have the same vehicle, and that happens to me when I use Mobil or another brand. I don't know exactly why this happens, the hesitation, but I try to stick with Chevron. 87 octane is all you need.

 

[allsounds]

Fuels with additives work best... Chevron, Texaco, BP, or you can add your own bottle if you're not using a detergent. There are other things that could be causing this hesitation also. We have the same vehicle, and that happens to me when I use Mobil or another brand. I don't know exactly why this happens, the hesitation, but I try to stick with Chevron. 87 octane is all you need.

OK, thanks! It's a small problem that probably is not really hurting much, it just bothers me.

 

[Donner]

There are some other things that need to be checked out in addition... but they are things that I know only from this site. You might wanna wait just a bit and you'll get some additional advice... (but I know, when it feels like it's going to stall out, you just think, "wha??" You know it's in great shape, but something just isn't running quite right) Good luck!

 

[allsounds]

There are some other things that need to be checked out in addition... but they are things that I know only from this site. You might wanna wait just a bit and you'll get some additional advice... (but I know, when it feels like it's going to stall out, you just think, "wha??" You know it's in great shape, but something just isn't running quite right) Good luck!

Yeah, I hear ya... thanks!

 

[Donner]

Any suggestions for Allsounds? Thanks!

 

[aldive]

Fuel filters are changed about every 25-30k.

Oh, really? Where did you get that information?

My last fuel filter change was with 70k miles on the filter, and it still looked brand new. See pictures at http://www.explorerforum.com/forums/showthread.php?t=164595&highlight=fuel+filter

 

[aldive]

usually i put regular in, every 4th fill up I put premium in... It is on a tank of premium right now.

Why do you use premium at all?

 

[Donner]

Recommended schedule...

Oh, really? Where did you get that information?

My last fuel filter change was with 70k miles on the filter, and it still looked brand new. See pictures at http://www.explorerforum.com/forums/showthread.php?t=164595&highlight=fuel+filter

Hi Aldive... It's the recommended change interim.

 

[aldive]

Hi Aldive... It's the recommended change interim.

Please, where did you see that?

 

[Donner]

Here you go...

Please, where did you see that?

http://www.explorerforum.com/forums/showthread.php?t=199764&highlight=service+schedule

This is the location... thanks guys.

 

[Donner]

I got my first Ex in 1994, my third in 2003. Although I don't do my own maint'nance, I do pretty good with the maint' schedules.

 

[Donner]

Any additional items that can be checked to alleviate the hesitation?

Use of premium: Some stations include detergents in their 89+ octane brand, but not in their 87 octane. As mentioned earlier, 87 octane w/detergent is all that's needed. I believe Shell includes detergents in their 89+ octane brands.

http://www.shell.com/home/Framework...rists/fuels/optimax/optimax_faqs_ga_1602.html

 

[Donner]

Is that info incorrect?

Please, where did you see that?

Any problems with the information listed? Thanks!