02 XLT P0430 Code

[khalidmo81]

I have an 02 XLT, after changing the plugs, wires and air filter I started getting this code. I have already changed the cat on bank 2 and the rear O2 sensor as well. I cleared the code and it has not come back yet but the CEL will stay off for a day or two. Hopefully that does take care of the code. I will let you guys know if it did.

The problem is the engine is still idling somewhat rough almost like the it is misfiring. I checked all the plugs again and they look fine. I am thinking a vacuum leak somewhere. Any ideas?

 

[ExPlOrErImPoRtS]

found this

P0430 indicates bank NO. 2 catalyst system efficiency is below threshold
bank 2 is on the driver side
check for an exhaust leak
oil contamination
cylinder misfire

 

[khalidmo81]

Thanks for the response. I know there was a misfire for sure, when I changed the plugs I reversed the cables for 5 and 6 and drove about 15 miles to a friends shop on it that way. I corrected that and changed the plugs for 5 and 6 as well.

One thing I noticed yesterday, when I unplug the MAF sensor the engine smooths out. I will be cleaning it later tonight and let you know the outcome. Thanks again!

 

[khalidmo81]

Oh yea, the guy at the shop was not sure where bank 2 was and he changed the cat on bank 1. I went back to him cause it did not make sense to me, he check the manual and gave me a free cat on bank two. Two cats for the price of 1.

 

[SyberTiger]

Make sure the problem isn't this: CEL Lights and Rough Idling

 

[khalidmo81]

SyberTiger I actually spent over an hour reading through that post Saturday night hoping that is what it was. When I checked it Sunday morning it looked fine, but I plan on replacing it anyway and save a headache down the road.

 

[mainevein]

Had a similar problem with my 02 mountaineer was a ptfe (or something like it) valve.

 

[khalidmo81]

I think you are talking about the DPFE Valve. I will check that out as well. Got a lot to do now when I get home.

 

[khalidmo81]

I cleaned the MAF. Check the elbow again at the PCV valve and the other end. I could not find the DPFE. The truck is still idling rough, but no CEL light it has been a couple of days.

I did notice when I shut the car off there is a sound like air is escaping, kinda like opening a bottle of soda after shaking it. That sound is coming from the back towards the bottom but I could find exactly where. Just wait til the weekend to look at it. Thank you all for your suggestions.

 

[RickM]

I'm putting my money on the elbow (post #5). Every symptom is typical of this failure.

 

[BigRondo]

I think you are talking about the DPFE Valve. I will check that out as well.

I could not find the DPFE.

I recently changed my DPFE Sensor. Mine was throwing P0401. I got it at AutoZone for around $40. It took me about 2 minutes to change with no tools required. Just remove the electrical connector and pull it off the 2 rubber hoses, it's not screwed or bolted to anything. I don't know if you have the V6 or the V8. Location with the V6 is on the passenger's side at the firewall (see pics below). Location with the V8 is behind the throttle body adapter. You have to remove the engine cover to access it.

Here is a scan from my Haynes Manual, location with V6:

Here is a picture of mine, V6:

Hope this helps out!

 

[khalidmo81]

Thanks for the pics I found the DPFE, it looks like it was replaced by the previous owner. Same goes for that hose that connects to the PCV valve, it looks like it was replaced as well.

I may have found the solution, I cleaned the IAC the rough idle was still there. Then I cleaned the throttle body, it was covered with carbon deposits, and the idle smoothed out considerable. Gonna try the sea foam i keep reading about here, found it at NAPA when getting throttle body cleaner. I let you guys know how that goes.

Thanks everyone for your help, I would've gave up if I didn't find this forum.

 

[BigRondo]

Bump for an update.....