lol its a large auto parts chain (only ?? ) in the north east i guess.

 

kwing, did you ever pull the codes. It's the easiest thing on earth to do. You can read about it here http://fordfuelinjection.com/index.php?p=13. All you have to do is ground the STI plug. What I did was get a length of wire (6ft or so) and crimp on a spade terminal on one end and an aligator clip on the other. The spade was too wide so I filed it narrower until it fit. I plugged the spade into the STI plug and hooked the alligator clip to the battery ground. You get in the car and turn the key on but engine off (KOEO) and count the blinks. You have your codes in 5 minutes.

 

Yep. My codes were 172 (Heated Oxygen Sensor, Lean Bank #1) and sometimes accompanied by 334 or 328 (EGR voltages not right or unexpected)

kwing

 

Sorry kwing. I just re-read your original post and you did have the codes in there. I had the 327 and 328 codes that all went away with a tune up. I was at fordfuelinjection.com earlier today reading up on the EGR and it says:

"The EGR system recycles burnt exhaust gasses into the intake. This lowers the amount of fuel needed, and lowers toxic Nitrogen Oxides in the emissions. The EGR only operates at highway cruise conditions."

I bought a vacuum pump the other day and the users manual had a EGR description in it. It also said that the recycling of burnt exhaust gasses into the intake was to cool down the combustion chambers. Note the "highway cruise conditions" in the EGR function description above. And you said you made it go away once by cleaning the EGR. Sounds like you either need a new EGR or it is not being properly actuated by the vacuum. Sounds like it's not kicking in at highway cruising speeds and your combustion is overheating.

Think about what your codes are telling you. Overheating O2 sensor and incorrect EGR readings. If your EGR isn't doing it's job then you would have incorrect EGR readings and some overheating.

Someone on the thread I started thread told me that the EGR should fully open at 6-8 in Hg. Mine was opening at 7 and the vacuum line was pulling 7 so I'm pretty sure that my EGR system is OK. If you don't have one you can buy one of these little vacuum pumps for $24 at Autozone. That's what I used to do all the vacuum measuring.

Its my opinion that your EGR needs replacing or you are not getting sufficient vacuum.

 

Thanks again. I managed to wrench the EGR off the intake and will analyze it further (I will put anti-seize on the threads!). It does pull the pintle up when I pull vacuum but I will check to see if the diaphram and other pieces are shot or clogged. As a precaution I will also replace the vacuum line from the EVP solenoid as well.

I will post the results soon.

kwing.