Went to work this morning and noticed my truck was running a little rough at 75mph down the interstate. Parked it and came out at lunch time and it was really missing badly and the engine light came on. When I strated to go down the road the light started flashing and black smoke was comming from the exhaust. Took it straight to the dealer it started to run better right as I got there. They called me a little while ago and said the computer said "Both banks are showing to be dead" They will have to put there engine man on it tomorrow. I assume no compression. It is a 04 F150 5.7 with 85,000 miles well maintained. I am worried sick now. Anybody have any idea what this could be. Both Banks. That would have to be some kind of bad sensor??????I hope. Thanks in Advance...
sonnyw22

 

I'm confused, 5.7= GM. Do you mean 5.4?

 

Sorry 5.4L

 

From the sounds of it I think they meant to say both banks are running rich and the oxygen sensor are dead. Or you have failed COP on both banks which is what ti sounds like based on your description. If the engine was dead you would not have made it to the dealership. Get better clarification from the Service adviser and if he cannot explain in detail what the issue is consider someone else.

 

I wouldn't be to worried at this point, What codes did they pull? It could be something simple as Richard said. Any intake mods? Just getting to much fuel for some reason. Codes would help and I'm sure they will diagnose the problem. But I believe your engine is fine. Black smoke means to much fuel and there are sensors that if faulty can cause that.
Edit- I need a new keyboard bigtime

 

No mods to the intake just a K&N filter. He did not give me the codes but I will get them tomorrow. Hope you are right. Any more ideas. Thanks for the help...

 

Over oiled the filter can contaminate the MAF sensor. PCM will indicate a lean condition and give more fuel. Could be off track, have to see what the codes are.

 

x2

I know that is the problem... if any of you want to replicate this issue, just unplug your MAF and drive your truck around. You'll see what I'm talking about.

Good job wrench007.

 

This may not make a diifeence but the last time I cleaned and oiled my filter was in June of 07. I do very lttle off road driving. I did check it last weekend,,,, Should I call and tell the dealer that the K&N is in the airbox????
Thanks once again guys.....

 

No they may try to blame it on that.

 

I wouldn't. let them diagnose, find the problem. If it is indeed the MAF sensor, I can tell you from experience cleaning it didn't work for me most of the time. We had a batch of bad air filters while I was working on the Mercedes in-line 5 cly 2.7 diesel. The air filters just caved in and contaminated the sensor. I tried many time to clean it using proper procedures and spray, and 90% of the time I had to replace it to cure the problem.

 

Here is some new info on my problem. I am being told that the right bank is misfifing on all cylinders. They are looking at some position sensor or a possible "jump time" issue. Surely it sould not have jumped time on one side.
Thanks in advance.....

 

Damn, sorry about the bad luck, Now I'm thinking a bad camshaft position sensor (CMP) on the RH side. Keep us up to date, hope that's all it is, simple fix. Good luck. Did they give you any codes that could help pinpoint the problem?
Hate my keyboard, going south. Thank God I got ieSpell.

 

I guess no new is good news. But they still have no idea what is going on. Thanks goys for all the help and I will let you know the codes or the result. I love this site........

 

sounds like a hung open injector to me....