Ok, I took apart my throttle body, cleaned out the carbon buildup on it, and the spacer.

It ran great and no problems for about 100 miles, then, instead of giving me the P0402 error, it's giving me both the P0401 AND the P0402 error.

It was told to me that the issue is probably the EGR position sensor? Does this sound right to everyone?

 

p0401-insuff egr flow, p0402 egr flow detected at idle. possible sensor, or stuck egr. Does not have a "position" sensor.

 

I had the similar codes throwing on my truck. Here's the thread from here that helped me out. It was my DPFE sensor that was the cuplrit. $36 and the truck was fixed. Hopefully this helps you out.

https://www.ford-trucks.com/forums/s...d.php?t=224616

Jason

 

If your passages are clear then the BIG HOSS man is correct. P ut on the DPFE sensor.

 

I have the same problem. I don't think my 96 Explorer XLT V8 has a dpfe. At least I can't find it. I think I see the EGR towards the back of the engine but its impossible to get to and see if dpfe is under it. Does anyone have any experience on this? Thanks

 

A 1996 5.0 uses a EVP sensor instead. It is bolted onto the EGR valve with either 3 screws or 3 nuts. Yup it's going to be a pain to replace.

 

I replaced the DPFE sensor and waited a few weeks before posting the results. So far, I've seen:

No more check engine lights
Better gas milage
Better acceleration
No more knocking when accelerating from a low speed
Better overall performance

Would the sensor really be a factor for all those things?

 

Racerguy: Do you think a new EVP sensor will fix the P0402 code? I've noticed the EGR valve is around $150. Not real cheap if I end of replacing it without a good result.

 

kc5deb yes it's possible that replacing the DPFE will fix all that.
When the check engine light is on the engine runs in "open loop" which means that different sensors aren't controlling the air/furl ratio, ignition timing etc. It goes into a failure mode and sets everything at predetermined values which is usually more gas, less timing advance.

youngphotons the EVP sensor can be replaced seperately from the EGR valve and shouldn't cost very much. Getting it scanned and tested at your dealer would be best to verify that's the problem. We used to replace lots of those. If the engine idles smoothly the problem is probably the EVP.