Totally Stumped - 2006 Explorer Engine Light

[MarinDuck]

Okay...so I am officially stumped. My explorer is (or maybe I should say "was") in great condition with around 120,000 miles on it. About 6 months ago, the check engine light came on and it is a little sluggish when under 3,000 RPMs. Also, the gas cap light comes on and goes off randomly.

I took it to our regular mechanic, who worked at the Ford Dealership for 20 years before opening his own shop a few years back. He pulled codes P0401 and P1408. He replaced the fuel cap, EGR Valve, and gasket. The engine light went off after clearing the codes. It passed the EGR test (ran twice) and a road test. He turned the car back over to me with no codes and the engine light off. However, the next day the light came back on 5 minutes into my drive after a cool start. I took it back and our mechanic says everything looks good, but the codes are back. He cleared the codes again, but the next day the same thing happened. He recommended we get a second pinion.

Therefore, we took the car to a second local shop. He cleared the codes and told us that the car appeared to be running fine. He recommended we take it to the Ford Dealer.

We dropped the car at Ford and they pulled the same codes (P0401 and P1408). The changed the EGR valve again indicating it "could just be a bad part". They also changed the EMS Assembly. Again the car passed the EGR and road tests and they returned the car to me telling me it was fixed. The next day, the engine light popped on again.

I returned the car to Ford and they indicated that P0455 was now also on in addition to the other two codes. However, when they ran an evap test and EGR manual test, everything "looks perfect". They let the car sit for 2 hours, 24 hours, and 48 hours and re-ran the tests and they passed each time. They returned the car to me and the next day the engine light popped on again.

I returned it again and they pulled codes P0303, 401, 457, and 455. They replaced the vent valve and Evap Canister vent value and reset the evap system. They reflashed the PCM to the latest update and programmed the PCM to the latest calibration. Installed a S/O vaccum line to VMV valve and re-checked. They replaced all the spark plugs and wires and they indicated that it is "perfect".

The next day, the engine light came back on and it is still sluggish, especially under 3000 RPMs. At this point, the dealer refunded my money for the above work and told me that they were sorry that they were not able to fix the problem. The indicated that I could try replacing the computer at my risk, but that would be around $3,500, which is approaching the blue book value of the car. They were very specific that they could not guarantee it would fix the problem, so I decided against it for now. My registration is up in August of 2017 and I am going to need to pass smog, so I have to get this fixed somehow. Any advice out there?

 

[Davidm53]

Welcome to the Forum.
You might mention what engine you have to help with your problem.
You could have plugged up Cat Converters. My 06/ 4.0 has original Converters and I will get a different opinion from various muffler shops.
They tap on them with a hammer and tell if the honey comb material is broken up inside.
I am no expert, but have learned a few things from ownership.
The 4.0 has 2 and they around $300 each. One of mine has a rattle but is running fine, so holding out.

 

[MarinDuck]

I have the 4.0. It does have original cats, so I will check that. Thank you for the tip. Keep you posted

 

[PotatoExplorer]

$3,500 for a new PCM seems way over priced... I believe you can get one around $300 if I'm not mistaken.

 

[MarinDuck]

Yeah. They are probably trying to make up for all of the previous stuff they ended up giving me for free. No chance I am doing that at that price when the blue book is around $3500 for the vehicle.

Does a computer issue seem likely? If so, will probably just unload it as a parts car when smog is due.

 

[PotatoExplorer]

Yeah. They are probably trying to make up for all of the previous stuff they ended up giving me for free. No chance I am doing that at that price when the blue book is around $3500 for the vehicle.

Does a computer issue seem likely? If so, will probably just unload it as a parts car when smog is due.

It could be possible, especially since it seemed like you, your mechanic and multiple dealerships exhausted every other possibility? But honestly your guess would be as good as mine.

Here's a thread I found a month ago where the OP had some weird issues and ended up being a faulty PCM.
http://www.explorerforum.com/forums...-throttle-35-45mph-ecm-vacuum-erratic.412639/

 

[Mitchs07explorer]

My check engine light kept popping on a couple years ago but the codes I were getting were small evap leak codes. I changed my gas cap with the correct motor craft cap. That didn't do it, so I made sure there was no leaks in my evap system and there weren't. Ironically it was time to change my fuel filter so I did with a WIX fuel filter from oreillys, nice quality American made filter. I immediately got improved power and my check engine light hasn't come back on since. For a cheap fix I would give the fuel filter a try it might work for you.

 

[Mitchs07explorer]

My check engine light kept coming on always throwing the same small evap leak code. I changed the gas cap with a Ford gas cap and still had same issue. It continued until I changed my fuel filter, I felt like I was getting quicker acceleration too. Sounds like you've tried everything but that. Pick up a Wix fuel filter from O'Reilly's and see if that does the trick.

 

[wunderland]

Okay...so I am officially stumped. My explorer is (or maybe I should say "was") in great condition with around 120,000 miles on it. About 6 months ago, the check engine light came on and it is a little sluggish when under 3,000 RPMs. Also, the gas cap light comes on and goes off randomly.

I took it to our regular mechanic, who worked at the Ford Dealership for 20 years before opening his own shop a few years back. He pulled codes P0401 and P1408. He replaced the fuel cap, EGR Valve, and gasket. The engine light went off after clearing the codes. It passed the EGR test (ran twice) and a road test. He turned the car back over to me with no codes and the engine light off. However, the next day the light came back on 5 minutes into my drive after a cool start. I took it back and our mechanic says everything looks good, but the codes are back. He cleared the codes again, but the next day the same thing happened. He recommended we get a second pinion.

Therefore, we took the car to a second local shop. He cleared the codes and told us that the car appeared to be running fine. He recommended we take it to the Ford Dealer.

We dropped the car at Ford and they pulled the same codes (P0401 and P1408). The changed the EGR valve again indicating it "could just be a bad part". They also changed the EMS Assembly. Again the car passed the EGR and road tests and they returned the car to me telling me it was fixed. The next day, the engine light popped on again.

I returned the car to Ford and they indicated that P0455 was now also on in addition to the other two codes. However, when they ran an evap test and EGR manual test, everything "looks perfect". They let the car sit for 2 hours, 24 hours, and 48 hours and re-ran the tests and they passed each time. They returned the car to me and the next day the engine light popped on again.

I returned it again and they pulled codes P0303, 401, 457, and 455. They replaced the vent valve and Evap Canister vent value and reset the evap system. They reflashed the PCM to the latest update and programmed the PCM to the latest calibration. Installed a S/O vaccum line to VMV valve and re-checked. They replaced all the spark plugs and wires and they indicated that it is "perfect".

The next day, the engine light came back on and it is still sluggish, especially under 3000 RPMs. At this point, the dealer refunded my money for the above work and told me that they were sorry that they were not able to fix the problem. The indicated that I could try replacing the computer at my risk, but that would be around $3,500, which is approaching the blue book value of the car. They were very specific that they could not guarantee it would fix the problem, so I decided against it for now. My registration is up in August of 2017 and I am going to need to pass smog, so I have to get this fixed somehow. Any advice out there?

 

[wunderland]

My 06 v6 was purchased 7/16 w/112K and chk eng code that indicated cat converters were bad. Since I live in an area w/no emissions inspections required, I have just ignored the light for the past year. In all other areas the engine performs well and no problems experienced. Now have 135K.....chk eng light still on.....no other issues.
If Athens Ga required emissions testing, I would have to install new converters. Thankfully that's not necessary.
In order to pass smog you may have to replace cat converters.

 

[boominXplorer]

There could be an issue in the engine harness. I have seen a bunch of issues where the outer coating comes off the wires near the ends of plugs.