Truck is a 05 6.0L with 128,000 miles. I recently bought the truck. Before I could change the fuel filters my engine light came on. I immediately went and bought new fuel filters. Due to not having the correct tools I was only able to replace the secondary filter. After replacing the secondary filter the light went off and I thought all was well. The next morning the light came back on on my way to work then went back off sometime around 10:00 and stayed off the rest of the day. Now again this morning the light is back on. Do you guys just think it's because I didn't replace the primary filter yet? BTW - I am planning on replacing it ASAP.

As I'm typing this I restarted my truck and the light is off again. The light doesn't flash at all, it just comes on for a long period of time then goes off for a long period of time. The truck did sit for 3 three weeks without being started before I bought it.

Do you guys just think it's a filter issue or a dirty EGR or should I take it back to the dealer? I'd rather replace the filters and clean the EGR then take it back to the dealer.

Thanks,

Mike

 

You need to check for codes. Guessing will get you no where.

 

I'm guessing that when the light is off I won't get a code. So its just a game of luck to have a code scanner when the light is on?

 

Usually a historical code will remain after the CEL light has gone out. The sooner you read the codes after the light goes out, the better your odds of finding the code. But it should be there for a good long time.

 

Besides the codes you also need to get that primary filter changed. I also hope you are using only OEM filters or you are defeating the purpose.

 

yeah i'm using motorcraft filters

 

I stopped by O-Reilly's Auto Parts on the way home tonight to use their scanner. It came up with the code P0405, which as you all know is the EGR valve. I asked the guy working about taking the valve off and cleaning it like has been mentioned on this forum. He said it's impossible to get the valve completely clean and recommended putting Seafoam in my fuel. What do you guys think about this? Should I try the Seafoam and leave it be or pull the valve off and clean it? I'm leaning towards pulling it just because I'm curious what it looks like.

Thanks,

Mike

 

I would try cleaning it and use carb cleaner not brake cleaner. There are threads on that and I think the tech folder may cover it.

 

You can definitely get the EGR valve completely clean. You just don;t know if that fixes its performance or not. The issue could be in the actuator. Cleaning is worth a try. As 69cj says, the Tech folder has threads on "how to do it".