So Ive had a misfire since I started driving the truck again. HAd the same issue last winter and replacing the wires solved it for a little while. I went to autozone and had it scanned and they found the following codes:

P0141 O2 bank 1 sensor 2
P0401 EGR system fault
P0307 Misfire cyl 7
P0304 Misfire cyl 4
P0302 Misfire cyl 2

I bought new coils and wires and installed them to no avail. So I swapped back to my original coils but kept the new wires on.

The whole issue is this...

The truck is low on power. If i take off slow you barely feel the misfire but if I stomp on it you can feel it more and it takes a while to get up and go. Im thinking the O2 sensor reading the way it is is being caused by a clogged cat hence the reason it takes so much to get up to speed and keep that speed. The EGR I will pull off and clean and see if that helps but I doubt it. Id rather just rid myself of it.

Anyone have any ideas before I rip ALL my hair out lol.

 

Gaskets? The P0401 code is what I;ve found to be normally for lack of a vacuum in your egr and throttle body. Check your spark plugs? Just an idea. If you can find the sensor, I think you can check it by measuring the voltage of it. I think. If I'm correct, it possibly might be around 5v. Again might be wrong with the O2 sensor. The P0401 code also could be a sensor. Find it and check that one. Should be coming in from behind the throttle body. You might want to research it a little more but I've heard you can use and needle or a safety pin and stick it barely into the sensor wire to get the measurements. Maybe try cleaning the throttle body. Atleast check the ports and valve in it. Just make sure you get a good seal back on your gaskets(preferably new) Really all you can do is eliminate problems. Good luck. If I think of something else I'll pm you.

 

Plugs are brand new. Can't seem to find a PN for the TB gasket so I'm going to have to be very careful with pulling it off to clean the EGR. As for the O2 code, I'm picking up a new O2 tonight and changing it out. I'm hoping with these changes and the new wires it will run better. I did notice there's no backfire popping noise while cruising now though so I may have fixed the misfires. I will keep everyone updated.

 

The o2 sensor code may be as a result of the misfire. Bank 1, sensor 2 means passenger side, downstream. The downstream sensor is used to monitor cat. efficiency. Misfiring cylinders change everything with regard to o2 sensores since the oxygen doesn't get consumed during misfire. It then flows past the sensor and causes a low 02 voltage.
I would fix the misfire before replacing any sensors or even the EGR. Check for vacuum leaks. Check fuel pressure. Check for cracks in air intake system between MAF and throttle body. I would start with this.

 

Your right udder but the misfire seems to be gone and now what I have is a rough idle and sluggish power. I'm thinking I may have a clogged cat but I'm no 100% sure. It sometimes bucks at low rpms while driving as well. I have been through the intake tube from filter to TB and have also cleaned the MAF (using CRC MAF cleaner). The EGR being clogged could cause this as well. I have also replaced th fuel filter since I was told when I bought it, it was new which was BS since it was almost rusted through. So I may have to replace the fuel pump as well.

Just tryin to get ideas and input so all comments are welcome.

 

Still having the egr code?

 

Yes. I didnt get time to work on it yesterday so i will probably tonight

 

A vacuum guage can help diagnosing a plugged cat. If you think the o2 sensor is contributing, you can try disconnecting both front sensors and letting it run in open loop. It'll run a little more rich but it should run better (if the sensor is faulty). Also if you have access to a scan tool which can read live data, the long term fuel trim PID will tell you what the PCM is doing with the fuel trim (shortening or lenthening the injector pulse width).