bank 1 lean - bank 2 lean

[outlawwv]

i have an 03 explorer with v-8 -- engine will barely idle and is really rough runs good once wound up - have service engine soon light on - had it checked at advance and code said bank 1 & 2 lean - seems like a vac line leak but i don't see anything cracked or unhooked - any ideas ?

 

[Donner]

Possible o2 sensor issues...

Let's see... I'll check real quick in search, but I'm thinking the o2s are the issues. How many miles on the Ex?

 

[Donner]

Check this out... there's a thread that suggests the spark plugs and wires may be the issue. (I had the link, I'll repost it here...

http://www.explorerforum.com/forums/showthread.php?t=200022&highlight=bank+1+2+lean

 

[aldive]

I seriously doubt that this is an O2 sensor issue.

Good luck in resolving the problem ....

 

[KINGY 99]

The Bank One And Bank 2 Are U O2 Sensors Replace Them, The Runnin Ruff We Cold Is A Upper Intake Manafold Leak Its Any Easy Fix After U Fix All That Ull Be Runnin Good, Kingy

 

[outlawwv]

thanks for all the info -- damn i hope it's not the plugs -- i told my wife that there was no way it was plugs or wires --

 

[Donner]

How many miles on the vehicle?

thanks for all the info -- damn i hope it's not the plugs -- i told my wife that there was no way it was plugs or wires --

If it is the plugs and wires, just don't say If she doesn't know a lot about vehicles, tell her the telnoid near the iradant went out...

 

[wchain]

02+ 4.6L V8 explorers don't have Plug wires. They are coil on plug.

Look at your PCV Hose assembly, particularly the rubber elbows.

 

[E.B. Cornburner]

Definitely a vacuum leak somewhere. It's almost impossible for both O2 sensors to crap out at the same time, besides, if they crapped out, it would set a different code, not one for a lean conditon on both banks.
The other thing that tips me off is that you mentioned a rough idle. That's when vacuum is high, so a leak at idle will cause the problems you mentioned. We just had one that had a major vacuum leak where the EGR pipe goes into the plenum. It was a 4.0, but same concept. Looks like the hot EGR pipe finally had its way with the plastic plenum and it crumbled away around it. Since this one was going to the auction, a generous gob of JB Weld took care of it. Had it been a customer's ride, it would have gotten a new plenum.

 

[wchain]

Definitely a vacuum leak somewhere. It's almost impossible for both O2 sensors to crap out at the same time, besides, if they crapped out, it would set a different code, not one for a lean conditon on both banks.
The other thing that tips me off is that you mentioned a rough idle. That's when vacuum is high, so a leak at idle will cause the problems you mentioned. We just had one that had a major vacuum leak where the EGR pipe goes into the plenum. It was a 4.0, but same concept. Looks like the hot EGR pipe finally had its way with the plastic plenum and it crumbled away around it. Since this one was going to the auction, a generous gob of JB Weld took care of it. Had it been a customer's ride, it would have gotten a new plenum.

AMEN! My 5.4L Navigator had the same issue, Lean in both banks, and rough idle. One of the Elbows in the PCV system had eaten a hole itself. bought a new elbow at FLAPS and installed it in the parking lot.

 

[outlawwv]

thanks for all the info -- when i bought my used explorer a year ago i bought one of those overpriced warranties and tomorrow the dealer is sending a flatbed to come and get it -- it is at it's worse at idle (it'll barely run surges shudders and eventually dies) can't see hear or find a vaccum leak -- last night the overdrive light was flashing and it seemed to be in neutral had to put it in "3" to get home and the abs light came on -- ever since i've owned it the four wheel drive made a terrible noise when it kicked in and the heater blows hot air on the floor when on defrost -- so i'm gonna pay the $100 deductible take their loaner car and do our x-mas shopping while they fix it -- i'll let you know what they come up with

 

[E.B. Cornburner]

Definitely do let us know. Just in case I run into one with a similar problem, it's nice to have mental notes.

 

[E.B. Cornburner]

AMEN! My 5.4L Navigator had the same issue, Lean in both banks, and rough idle. One of the Elbows in the PCV system had eaten a hole itself. bought a new elbow at FLAPS and installed it in the parking lot.

Very common. The oil vapors attack the rubber elbows, and eventually trash them. I've fixed many a Windstar with the same problem. This is the first on a 5.4 that I've heard of though.

 

[mkewl]

prob this is the fix

Check the crankcase elbows and vac leaks. Most causes with this code is an intake leak or the MAF sensor is dirty. Taking it of and sparying the small wires in the sensor were air flow is with carb spray and then blowing that off easly with shop air.

 

[outlawwv]

got the ex back from the shop thursday - it was the pcv hose that was cracked causing engine to run bad -- speed sensor in rear wheel causing abs light to be on -- they couldn't get the 4 wd to make a noise when auto engaging -- said there was nothing wrong with heater yet it still blows hot air out on floor when it is set to defrost -- well at least they fixed some of it

 

[Donner]

Does it not allow air to pass at all through the defrost vents (by the windows and the windshield)? There has to be something wrong, mine doesn't blow air on the floor unless it's set to do that.

 

[outlawwv]

Does it not allow air to pass at all through the defrost vents (by the windows and the windshield)? There has to be something wrong, mine doesn't blow air on the floor unless it's set to do that.

when set to defrost air blows out the defroster but still comes out on the floor - it has done that since i got it - the guy who worked on it said it was because of vac leak on motor - i told him it did that before that problem came about but he said it was working fine - i guess they'll just have to work on it again

 

[Donner]

If there's no difference between settings...

Is it possible there's a vent door malfunction between the two settings? What's it look like under there? Would that vent be visible by looking under there while someone changed settings? I'm curious too... I think I'll try and have a look too.

 

[E.B. Cornburner]

they couldn't get the 4 wd to make a noise when auto engaging

Try changing the fluid. Mine at ~88,000 looked like mud. Drained and refilled with fresh Mercon V, and the difference was astounding.

 

[wchain]

Check the crankcase elbows and vac leaks. Most causes with this code is an intake leak or the MAF sensor is dirty. Taking it of and sparying the small wires in the sensor were air flow is with carb spray and then blowing that off easly with shop air.

DO NOT use carb cleaner/throttle body cleaner/brake cleaner on the Mass Air "Fangs"!!!! They leave a deposit/film on the sensor. If you're going to clean it, use either Electrical Contact cleaner or specific Mass Air flow sensor cleaner.