Lean Code on 2000 Explorer

[Eggy44]

Hey guys, I'm new to the site and I have a 2000 explorer XLT with the 4.0L SOHC in it.
I have a few questions...I keep getting this lean code (p0171 and p0174-both B1 and B2 are lean) coming up on the scan tool and I can't seem to find out what it is. Here is a list of things I have done to the truck to try and fix it:
-Upper and lower intake gaskets
-checked all the vacuum hoses to the intake
-ran smoke to find any leaks around the gaskets
-also cleaned the IAC

can you guys help and try to figure this out. I know the gaskets are the #1 problem with these trucks but it keeps coming back

Thanks guys,

Jake

 

[ERUSH97XLT]

Hey, Eggy--

Check this out:

http://www.explorerforum.com/forums/showthread.php?t=225969

Lean codes are the WORST to diagnose. It could be anything air or fuel related. Mine turned out to be sparkplug. I would first clean/replace your MAF, then we can dive into more elusive issues.

Good Luck!

ERUSH

 

[chrisrace24]

i just failed inspection with the same code system too lean bank 1.. i was able to diagnose the problem as the idle air controle motor. you might want to look into that..on the ohv motor its located on the right side of the intake manifold

 

[Port]

def sounds like a maf problem. u can clean it with a little brake clean or with windex. spray the elements with the engine off and then cycle the key a few times to clean it off. the elements heating up will burn the dirt off.

 

[ERUSH97XLT]

Hey!

DO NOT USE BRAKEKLEEN!!! :thumbdwn::thumbdwn: It will destroy your MAF! I did it once... never again. Get a can of CRC's "MAF Sensor Cleaner". It's designed to not dissolve the filaments of your MAF. It's like... $5 if I remember correctly. This small price is well worth a $250 mistake.

Thanks,

ERUSH

 

[Eggy44]

Thanks for the responses guys

Ive cleaned the idle air control and that didn't help at all...my next idea was to get a cleaner for the mass air flow sensor. If that didn't work, the next thing was the EGR valve.

I've pumped smoke through the intake to see if there was any leaks and the truck was not running and there was smoke just pumping out the side of the EGR valve body...ive changed the gasket for that too but that didn't help either. Any ideas guys?

Thanks
Jake

 

[ERUSH97XLT]

Eggy,

Sounds like you might have found your leak. The EGR body is not supposed to leak. I would replace it. Do you have any other codes or pending codes directed to EGR flow or EGR leaks?

ERUSH

 

[Eggy44]

I have two speed sensors out but thats a whole other story so nothing related to the engine is wrong besides the two lean codes. Could it maybe be the Vacuum soleniod for the EGR on the left side of the intake mani? I'm pretty sure its the egr but I want to make sure that it before I start hanging $70 parts.
ERUSH97XLT thanks for the insight

Jake

 

[ERUSH97XLT]

Jake,

Was smoke leaking through the EGR "valve" or through the EGR "solenoid"?

Do you know how to test your EGR selenoid? If not, follow this link:

http://www.fordfuelinjection.com/?p=43

ERUSH

 

[Eggy44]

Jake,

Was smoke leaking through the EGR "valve" or through the EGR "solenoid"?

Do you know how to test your EGR selenoid? If not, follow this link:

http://www.fordfuelinjection.com/?p=43

ERUSH

It's leaking out of the bottom side of the polished part of the EGR valve...I have a feeling its that.

 

[ERUSH97XLT]

Sounds like you need to replace your EGR valve. Good luck getting it off though. You might need some penetrating oil, a blow torch, or both... check this out for some tips:

http://www.explorerforum.com/forums//showthread.php?p=2136631

Best,

ERUSH

 

[Eggy44]

Thanks ERUSH...thats probably what I'm going to do. It's going to be a pain in the ass though lol
wish me luck

Jake

 

[ERUSH97XLT]

No prob, Jake!

Let us know if that makes a difference! If not, you probably saved yourself some extra headache in the future... All in all, I bet this is the source of unmetered air tripping your lean code. If not, well... I guess we'll start from square one.

Good luck!

ERUSH

 

[mbird97x]

My 2000 4.0 SOHC was doing the same codes. Turned out to be the intake gaskets bad. Haven't had the problem since going on 4 years since changing them. Originals were a light green color and you could see the streaking where air was passing by. Replacements from NAPA (Victor-Reintz) were about 15.00 IIRC

 

[ERUSH97XLT]

Gary,

This has been a common problem among the SOHCs. I believe Jake replaced his gaskets, so that's why we ruled it out. Since smoke was escaping through his EGR valve, I'm thinking that's the source of the vacuum leak.

ERUSH

 

[96eb96]

http://www.aa1car.com/library/ford_lean_codes.htm
pay attention to the DPFE!

 

[Eggy44]

Hey guys, back again...I haven't changed that egr valve yet (money is a little tight) but I did do a fuel pressure test in my auto class and I only had about 35 psi in the fuel lines and the spec is about 55-65 psi. Do you guys think that might have something to do with the lean code coming up?

Just a thought.

Thanks,
Jake

 

[ERUSH97XLT]

Low fuel pressure will definitely create a lean condition. The easiest remedy is the replacement of the fuel filter. Have you changed it lately?

ERUSH

 

[Eggy44]

Yeah I have replaced it recently but i did talk to a ford mechanic that knows these particular trucks and he said that the EGR valve shouldn't leak at all out of the EGR body

Jake

 

[ERUSH97XLT]

Jake,

Yep. Sounds like your EGR valve is shot. When you get the money, replace it ASAP.

ERUSH