Service engine soon...

[Francisco1022]

I recently did a code reading at Autozone due to the "Service Engine Soon" to light up. From the reading I got back the codes P1401 and P0402.

P1401's definition explains:
- ECM detected the DPFE (EGR Pressure Sensor) sensor voltage higher than expected.
Probable cause:
- Failed DPFE sensor (EGR pressure sensor)
- Open or shorted circuit condition

P0402's definition explains:
- System Fault (Exhaust gas recirculation)
- The ECM has detected too much flow on the EGR system

Probable cause:
- EGR valve stuck open
- Failed EGR pressure sensor
- Failed EGR valve
- Failed EGR pressure sensor where applicable
- Failed EGR position sensor where applicable

I would like to know if I can do these repairs myself. By the list of the probabilities here it is hard to know what really is the problem. Has anyone had these same issues? Thanks

 

[HiImBrian]

Me. My mechanic told me the only way to fix it is to replace my fuel pump. The sensor is built into it. He also said its not really hurting anything so it's not really high on my list of priorities...

 

[Teejay4490]

Wouldnt he need to replace the EGR valve? I had this same problem with mine ill post a pic of it later

 

[BigRondo]

I recently changed my DPFE Sensor. Mine was throwing P1401. I got it at AutoZone for around $40. It took me about 2 minutes to change with no tools required. I changed it right in the parking lot! Just remove the electrical connector and pull it off the 2 rubber hoses, it's not screwed or bolted to anything.

Location for the V6:

Good luck!

Please keep us posted as feedback helps others reading this post looking for a fix to the same or similar issue!

 

[Francisco1022]

Thanks you guys. BigRondo, before you replaced the DPFE, did your Ex consume more gas than usual? And did this replacement take care of the "Service Engine" light, if you had one in the first place? HiImBrian, for me its consuming more gas than usual. Since this is the only problem its throwing me with the codes, Ill take a shot at repairing. My 02 Explorer is only 97K miles and in good shape, have it for almost a year and would like to keep it for sometime. So Ill need to replace the fuel pump, DPFE and probably the EGR valve...

 

[Limited02]

Thanks you guys. BigRondo, before you replaced the DPFE, did your Ex consume more gas than usual? And did this replacement take care of the "Service Engine" light, if you had one in the first place? HiImBrian, for me its consuming more gas than usual. Since this is the only problem its throwing me with the codes, Ill take a shot at repairing. My 02 Explorer is only 97K miles and in good shape, have it for almost a year and would like to keep it for sometime. So Ill need to replace the fuel pump, DPFE and probably the EGR valve...

At one point my Explorer started hogging gas like a ****, I took it to where I bought it since it was still under warranty and that was the problem. They replaced the DPFE sensor and my gas mileage went back up

Might want to look into cleaning out your IAC valve as well if the 4.0 has one.

 

[BigRondo]

BigRondo, before you replaced the DPFE, did your Ex consume more gas than usual? And did this replacement take care of the "Service Engine" light, if you had one in the first place?

I did have the check engine light. Replacing the DPFE did clear the light. I didn't drive it enough to notice a drop in MPG's. I replaced the DPFE right after the light came on.

 

[Francisco1022]

Ill change the DPFE tomorrow, and hopefully this is the cause of everything. Will keep you posted. Thanks again.

 

[BigRondo]

Good luck. Fingers crossed.

 

[Teejay4490]

Lucky yall, the 05's it came as one whole unit and you have to replace the egr valve and dpfe sensor all in one.

 

[Wills05xlt4x4]

Lucky yall, the 05's it came as one whole unit and you have to replace the egr valve and dpfe sensor all in one.

exciting news....
I'm sure those are very affordable......

 

[BigRondo]

Yeah, for all the crap with the '02's we got lucky in a few areas. Like the DPFE, 4x4 Control Module, & no drive by wire!!

Every cloud has a silver lining!!

 

[Teejay4490]

Well when the shop did mine it was 343 bucks. ****ted out at 95,495. And I drove it around forever without it being fixed I never noticed any problem with gas.

 

[fr0st m0nkey]

I've been driving around with mine on for the same code for a few months now. I took it to the stealership and they charged me $150 to flash the ECU which supposedly was going to fix it but it came back on after a few days and I didn't take it back. Before I took it to the dealership I had a guy from craigslist come read my codes and give me his input. He said it was a sensor problem and not to worry about it. I think my gas mileage has been negatively impacted by this but I've also got close to 18 mpg on the highway one tank so who knows. Thanks for the info Rondo!

 

[Francisco1022]

Apologies for not keeping up with the post. Ive been busy with school and work lately and today I FINALLY replaced the DPFE Sensor. Computer was reset and service engine has been off ever since. Thanks to all for the help!