p0701 p0704 codes again

[Rich Lacilla]

So it's my turn for the p0701-p0704 codes for the second time. First time happened about 2 years ago, turned out to be the infamous cracked elbow. With the help of this forum it was promptly diagnosed and fixed. So about 3 months ago the same codes reared their ugly heads again.

Since i replaced the PCV elbow 2 years earlier I was doubting it could be the same problem.

I removed the entire PCV hose assembly and inspected it, no cracks found at all.

BTW, I should add that I have an '03 Sport Trac job 2 with 198,000 miles.

I then proceeded to replace the PCV valve and then eventually the MAF sensor. Still no luck.

I figured the intake manifold gaskets were the culprit. Even though I'm capable of doing the repair myself I didn't really have the time to deal with it. I needed to get it fixed to pass CT emissions

so that I could renew registration. I brought it to my local repair shop and after diagnosing the codes themselves they came up with leaking intake manifold gaskets and leaking exhaust gaskets before and after the cat. They quoted me $300. parts and labor plus tax to do both, which I thought was extremely fair:banana:. They did the repair and I brought it to emission testing the next day and passed. I was no more than 1/2 mile down the road after testing when the CEL came on again:angry:. Same codes so what is next on the list to do?

 

[swshawaii]

I believe the DTC numbers are usually p0171/174 for the PCV elbow. I'll let the experts help you here.

 

[Yardsale]

And there's this:

 

[Rich Lacilla]

Sorry guys, I mixed the numbers up when I typed them. The codes were definitely for lean bank 1 and lean bank 2 and the service center also came up with those when they read the codes. They also told me they checked all the vacuum lines. The truck is idling fine and has more power since the intake gaskets were replaced. So what are the next logical things to check.

 

[scott degroot]

I would take it back to the shop that "diagnosed" it and tell them to try again.

 

[Richard Toms]

o2 sensors? Maybe...



I got almost everything replaced on mine before I found out it was just the o2 sensors. I hit 182k miles on my 04 before I replaced the infamous elbow/line and there wasn't anything wrong with the one that was from factory. Replaced MAF, Intake, coil pack/wires/plugs, upper/lower intake gaskets, EGR valve. Ended up being o2 sensor.

 

[Hector Colon]

Please let me know what you find out. I have the same problem, but mines a Gen1/Job1, no elbow. Replaced the intake manifold gaskets, no luck.