question from the new guy.

[chopped49]

My dad owns an Explorer and recently the check engine light came on. well, he of course had to get it emmisioned so he took it down and it failed (obviously, the light was on) they did hook it up to a scanner and told him that the left bank was running lean.

Is this due to an o2 sensor? I'm pretty sure the 4.0l has o2 sensors on both side of the engine (in the exhaust manifolds) am I correct?

I'm just trying to help him get the car running back to normal, without a light and this weekend is the only chance i'm gonna have to help him get it running

thanks!!!
Seth

 

[Ray Lobato]

Welcome to the site.
You are correct that it probably is an O2 sensor.
Just change that little puppy out, reset the computer and you should be ready to go. You might also want to clean the MAF sensor too. There is a writeup in the Explorer TIPS on how to do this.

 

[chopped49]

thank you very much!!!

one last question though, how do you reset the computer? unplug the neg. battery terminal for a while?

 

[rpenner54]

Originally posted by chopped49
thank you very much!!!

one last question though, how do you reset the computer? unplug the neg. battery terminal for a while?

Yep! Disconect the battery for 15 minutes and everything should be all cleared.

 

[Robert]

Another thing not mentioned is if he has the SOHC, a lean condition on either bank could also be due to leaking lower intake manifold o-rings. Ford extended the warranty on them to 6 years/72K miles. The codes you will get are either a P0171 (short term fuel trim lean bank 1) or P0174 (short term fuel trim lean bank 2). What was the actual code number? It's much cheaper to have ford replace the o-rings at no charge than it is to replace $60 O2 sensors. If he has the SOHC, it has 4.

 

[chopped49]

his code is infact 0174 system lean on bank 2.

so this is an oring? where is it at? is it tough to replace? (I think my dads ride has over 72k miles)

Thanks!!!
Seth

 

[Robert]

It is very likely the o-rings. It is not just one, but six. There are 6 o-rings between the lower intake manifold and the engine block. The Ford book lists a little less than 3 hours to replace the o-rings and the camshaft tensioner which is covered by the same ONP. I paid an independant shop about $150 to replace my o-rings before the warranty was extended. If your Dad is out of warranty, Ford will charge about $300-$350 to replace the o-rings. If he is close to 72K miles I would see if they would offer any assistance. My past experiences with Ford Service though leads me to believe they won't. Your Dad should have gotten a letter from Ford back in November 2000 explaining the issue and the extended warranty. Of course if he wasn't having any problems with it back then, it wouldn't have meant much to him at the time.

 

[chopped49]

any writeups on this procedure anywhere? I'm all abotu saving the old man some dough...he put up with me for 18 years, it's the least I can do for him

 

[Robert]

Get a subscription to alldata.com for about $25 for a year. You can then download the procedure that the ONP describes. It still makes several references to the Ford Factory Service Manual but most mechanically inclined people should be able to follow the ONP only. If all you are going to replace is the o-rings, then it is just a matter of getting all of the parts off the top of the engine and putting on the new o-rings. The o-rings themselves should be pretty cheap. I think my repair shop charged me less than $10 for parts.