My truck is an 04 F150 (Heritage) STX, V6 4.2, 2WD.

I seem to have different codes than the other topics I've seen so I'm not sure if mine are the manifold gaskets or not, but to me the symptoms look right.

It runs rough on cold days until the truck warms up. It used to not start the bad running until the temp got into the 30's (that was 2 or 3 years ago). Nowadays if the temp is in the 50's it will run rough.

Last year I had the truck in the shop (not Ford) and they replaced the mass air flow sensor, all 4 02 sensors, battery (it needed to be anyway), spark plugs, wires, coil packs. He checked for vacuum leaks and didn't find any. I think he checked the EGR valve and possibly something else. At this point he was ready to replace the computer, but after that $1000 I couldn't justify the cost of the computer especially since I had heard of the intake manifold gaskets on some V6's.

Codes are:
0171
0174
2195
2197
Not sure why it lists these again as pending, but it does.
2195PD
2197PD

So do you all think the manifold gaskets would fix my problem too?

Thanks

 

The gaskets are the most likely fix for the 171 &174, along with other possibilities.

What are the other two codes? Depending on what they are it may send you looking in another direction. I looked on the DTC lists and couldn't find them.

 

2195 and 2197 are the other two. Whenever I first got them, I looked them up and I think they were lean codes.

 

Both front O2's stuck lean. Find your vacuum leak.

 

glc, are you saying 2195 and 2197 means it is a vacuum leak or all the codes?

Oh yea, I can deal with having codes, but this running rough problem needs to be fixed. It has got considerably worse over 3 years.

 

No, the 0171 and 0174 are pointing towards a major vacuum leak. Getting those cleared may clear the other 2. Gotta do this in sequence. A major vacuum leak WILL cause rough running.

Bad manifold gaskets are essentially the same thing as vacuum leaks.

 

I've also heard of the plastic plenum cracking before. Either way glc is right, find the source of the leak and it will probably clear the other codes.

3 years? sounds like it is leaking pretty good now. Might want to try the un-lit propane torch to find the leaks. Just direct the propane in the area you think there is a vac leak while the motor is running. A change in the idle indicates a leak.

Good luck.

 

Yep, mine has the plastic plenum. Last summer, I started throwing codes and it needed plenum gaskets and isolator bolts. Didn't you have to do the same thing, jgger?

 

^ Yup I sure did.

 

Thanks guys. Still deciding if I want to take it to the shop again or try to tackle it myself.

Getting a Ford Fiesta in the meantime as I need the better gas mileage.