My 1996 Explorer XLT is coding P0402 (excessive EGR flow at idle). It's been like that for 2 years. Now I want to repair.

I found a cracked vacuum line from EGR vacuum solenoid to EGR and replaced it. I also replaced the EGR vacuum solenoid itself and EGR position sensor. EGR is holding vacuum and engine bogs down when I manually activate it, telling me EGR is not the problem.

I don't think my model has a PFE manifold pressure sensor, just the position sensor that sits on top of the EGR. I have cleared codes by battery disconnect and by computer, but light still comes on after 2 drive cycles.

I would inspect or replace EGR valve itself if I could get it off. Mine is located on the back of the intake (next to firewall). The lower mounting bolt is tucked back in a little hollow underneath the valve, impossible to get to!

Does anyone have experience in changing EGR?
Any ideas about the pesky light?


Thanks.

 

What engine do you have in it?

 

Guessing by your description of it I'd say you have a 5 liter engine. The manual says to simply remove the bolts that hold the valve on. They always say that
Some engine I have had to heat and bend wrenches to get at the EGR pipe. Not fun.
The code you're getting could be caused by the EVP sensor (EGR valve position sensor) on the EGR valve. I've replaced quite a few of them on older engines. It's only 3 small nuts and not too much money. Might be a good try.

 

Sorry I just noticed you already replaced the EVP. My bad
Next thing to look for would probably be plugged EGR ports in the intake. Looks like you're going to have to remove the EGR

 

Thanks, I plan to pull the EGR tonight (cut a 9/16 boxend in half).

Got a new valve in case I need it, but I plan to clean, check & reinstall the old one (diaphragm is ok I know).

Any idea how worried I should be about breaking carbon residue loose & not getting it out (might get down into cylinders)?

Thx,
Laine

 

& yes, it is 302 V8.

 

Well, that wasnt it.

Now I've replaced EGR, EVR (solenoid), EPS (position senor) and a vacuum line, & I've STILL got the problem.

Electrical is next - trace sensor wires.

After that I give up!

 

Hey Laine,
Did you ever figure out your EGR problem and what was causeing it. I have the same 96 Explorer with the 5.0L engine and I am getting the same exact code. I was just about to order a new valve and sensor from carparts.com and replace them. I don't want to spend the money on these if I am still gonna get the code like you are. Also was it a b*itch to get the old Valve off or was it not as bad as you thought. Thanks