HELP!!! With all these codes and the descriptions of them being so vague I'm not really sure what to change. The truck is a 99 f-150 with a 4.2 v-6. It will crank but idles rough. It sometimes does it when its warm and sometimes cold. I cleaned the MAF the other day and it ran ok for a couple days and now its back to sounding like it has a souped up cam in it. One day it will have black smoke and one day it will have white smoke!! Can a bad O2 sensor cause the MAF error code or can it be the other way around? Any advice would be much appreciated and if any more info is needed to help make an educated guess on what to do let me know. I can't afford to start part swapping. Thanks in advance.

 

I also forgot to mention that when I unplug the MAF nothing changes. It still does the rough idle, spitting and sputtering. The order of the codes was P1121, P0102 then P0133.

 

Codes 1121 and 102 all involve the mass air sensor "circuit".
The code 121 involves the Throttle position sensor circuit.
Codes 131 and 133 involve the forward Ox sensor on bank 1, the pass side.
These codes tell me first there is a harness/power problem of some sort or a fuse is open or poor seating in it's holder.
Clear the 102/1121 and 121 first.
See if it clears 131/133.
If not that circuit may have it's own issue.
Check that all connectors are fully seated, look for harness rub or burn through.
Do not replace parts until proven faulty. It's just an exercise in expensive guessing.
Good luck.

 

I don't even have a clue where to begin that process. Any input on that would be fantastic. I changed the TPS and it feels like its a little better. It still kinda shakes and acts like its missing. How long will it take for the check engine light to come back on if that didnt fix it?

 

Respectfully, re-read my post.
I gave you the logic and format based on the codes and told you what to start with.
You changes a part after being told not to do so, then come back with a repeat of not knowing where to start.
I can't help you if feel you have to take this position.
Suggest you engage the services of a good shop.
The motor is a computer driven design. As such you must work on any issue from that point, using the code descriptions a set.
Good luck.

 

Well I was referring to the actual process of tracking down the problem in the wiring. Like any tricks in you may have picked up over the years, a good place to begin or any input on how to check things with a multimeter. Don't mistake my frustration and lack of knowledge about wiring to be unappreciative. I do appreciate the help. I went through all of the relays, fuses and plugs and everything is seated firmly. There is no sign of any wires being rubbed or worn through. Any suggestions next?

 

There should be a red wire going to the MAF sensor. It is the 5 volt reference signal for the MAF and the TPS. Look for corrosion in the wire at or near the MAF. Check the voltage with the key on.

 

Also, no bad sensor will ever make WHITE smoke. White smoke is coolant in the combustion chamber. Someone keep me honest here, but I thought I remembered the V6 being prone to intake manifold leaks.

How does your coolant level look? Did these codes happen all at the same time or has it been gradually getting worse and you finally decided to check it?

 

The bad V6 gaskets were in 97 and early 98's, the 99 should be fixed. However, you do need to do a compression test and test the coolant for hydrocarbons. Is it using coolant?