2000 Explorer XLT 4.0 SOHC

[KVANDENBRINK]

Hello, Recently my 2000 xlt with the 4.0 SOHC has been stalling when idling. It will start fine, drives seemingly fine for the most part (maybe a little sluggish when accelerating). But whenever I just park it and leave it to idle for more than 10 minutes or so it will stall itself out. It almost sounds like it isn't getting fuel. Once it stalls it won't start again for about an hour. I've ran my scanner and it shows it is running lean bank 1 and bank 2. I thought maybe I had a bad fuel filter so I replaced that but the problem still persists. Any idea where to next look? The scanner showed that the fuel pump was on, and that the iac had no errors.

 

[Rick]

Just guessing that the IAC may be dirty and not functioning properly.

Just cleaned IAC

Ok this is just a small informational thread to let everyone know how easy and how much of a difference cleaning your IAC makes.. First off I have a late model 1997 (pre-98 features).. with the 4.0 SOHC. My IAC was located under the black SOHC cover on the top middle of the engine (4 small 7mm...

www.explorerforum.com

How to: - IAC valve cleaning thread (w/pics)

Have you ever noticed a loud hum and/or whine (whining) coming from your engine bay? Or more specifically your intake area? Or does your engine have a hard time holding the idle? Well, more often than not, this is due to a dirty IAC Valve. Since everyone is always asking about it, hopefully...

www.explorerforum.com

 

[KVANDENBRINK]

Just guessing that the IAC may be dirty and not functioning properly.

Just cleaned IAC

Ok this is just a small informational thread to let everyone know how easy and how much of a difference cleaning your IAC makes.. First off I have a late model 1997 (pre-98 features).. with the 4.0 SOHC. My IAC was located under the black SOHC cover on the top middle of the engine (4 small 7mm...

www.explorerforum.com

How to: - IAC valve cleaning thread (w/pics)

Have you ever noticed a loud hum and/or whine (whining) coming from your engine bay? Or more specifically your intake area? Or does your engine have a hard time holding the idle? Well, more often than not, this is due to a dirty IAC Valve. Since everyone is always asking about it, hopefully...

www.explorerforum.com

I've tried cleaning the iac a couple months ago. I could see the iac being bad causing the vehicle to stall at idle. But the not being able to start it for an hour or more seems like a weird side effect if that was what was wrong. That was why i was looking into the fuel system to begin with.

 

[KVANDENBRINK]

I've tried cleaning the iac a couple months ago. I could see the iac being bad causing the vehicle to stall at idle. But the not being able to start it for an hour or more seems like a weird side effect if that was what was wrong. That was why i was looking into the fuel system to begin with.

I've attached two different scanning results I've gotten. The one showed a small evap leak but the next time I drove and scanned it didn't pop up again. So I'm not sure exactly what that would mean.

 

[410Fortune]

Lean both banks is usually bad intake o rings on a sohc engine

Your 2000
Has upper and lower plenum o rings and they likely need to be replaced. They dry up and start leaking. It’s a pretty straight forward job
To replace them

Checking fuel pressure is not a bad idea either

How
Many miles on the ol 2000?

 

[KVANDENBRINK]

Lean both banks is usually bad intake o rings on a sohc engine

Your 2000
Has upper and lower plenum o rings and they likely need to be replaced. They dry up and start leaking. It’s a pretty straight forward job
To replace them

Checking fuel pressure is not a bad idea either

How
Many miles on the ol 2000?

There are about 120k miles on it.

 

[410Fortune]

Had the fuel pump ever been changed?

I can guarantee those 24 year old intake on ring gaskets are dry and leaking

 

[KVANDENBRINK]

Had the fuel pump ever been changed?

I can guarantee those 24 year old intake on ring gaskets are dry and leaking

Fuel pump hasn't been changed yet. Unfortunately from what i understand with these lean codes there are a lot of different things that could he causing them. That's why I came here. I'm trying to rule things out and also not dump a bunch of money into something that it might not be.

 

[410Fortune]

Okay well I’ve been working on these trucks since the sohc engine came out
I have about 6 of them outside right now

I have solved lean code on both banks about 30 times on sohc engines with new intake o rings
But before I do that work I also check fuel pressure

Intake gaskets are about $25
It takes me an hour to do upper and lower plenum on a 97-02 sohc


Stock fuel pumps last about 120-160k miles but it has also been 24 years

Your lean codes are on both banks
Lean means the oxygen sensors have detected a lean condition and the computer has attempted to add fuel to solve it and was unable. So you get codes

Lean codes first thing to do is check fuel rail pressure cold and warm, especially when the truck is acting up.
Spec is 64 psi at the rail

 

[KVANDENBRINK]

Okay well I’ve been working on these trucks since the sohc engine came out
I have about 6 of them outside right now

I have solved lean code on both banks about 30 times on sohc engines with new intake o rings
But before I do that work I also check fuel pressure

Intake gaskets are about $25
It takes me an hour to do upper and lower plenum on a 97-02 sohc


Stock fuel pumps last about 120-160k miles but it has also been 24 years

Your lean codes are on both banks
Lean means the oxygen sensors have detected a lean condition and the computer has attempted to add fuel to solve it and was unable. So you get codes

Lean codes first thing to do is check fuel rail pressure cold and warm, especially when the truck is acting up.
Spec is 64 psi at the rail

Thanks. I'll see if i can either buy a fuel pressure tester or borrow one. The engine has about 120k on it but was recently installed after the last one blew up at 170k via timing chain issues. I had a friend of of a friend install it and I'm wondering if when he assembles the intake manifold if he didn't replace the gaskets or didn't torque it down right and it might be leaking.

 

[J_C]

In addition to checking fuel pressure, another easy one is clean the MAF sensor. The fuel pressure gauge you can get as a loaner tool from Advance Auto Parts, Autozone, OReilly's, etc. OReilly's used to have a really short return period for their loaner tools before you owned it, IDK about these days.

However, I too, suspect the intake manifold gaskets.

 

[allmyEXes]

How long ago did your friend install the O-rings and did this problem start right after that or later? Maybe the PCV valve isn't pushed in to its hose properly or all of the way. It can happen or not during the R&R process of replacing the intake O-rings. Sometimes with a smoke machine this leak would show up.

 

[gatzdon]

A failing temp sensor could lead to easy starts when cold and hard starts when warm. Just one more thing to check (easy to check the ECT with forscan and an OBDII reader).