Need codes info - poor gas mileage

[Irish Pride]

I just bought a 93 ATX this week and its running lean and getting crappy mileage. I'm averaging 16mpg city, and 20mpg hwy. The CEL comes and goes the whole time while driving. It is lit more than not.

I pulled the codes on it and this is what i got. I need help figuring out what they mean and what to do next.

KOEO

335 - DPFE sensor voltage higher or lower than expected.
522 - Indicates vehicle in gear.

stored codes

172 - HEGO sensor indicates system lean (RH).
176 - HEGO sensor indicates system lean (LH).
214 - CID circuit failure.

I tried the KOER twice but i couldnt get it to show any codes. I followed the procedure posted on shophoenix. Is it possible to get codes with one test and not the other?

Any and all info will be greatly appreciated.

 

[rubydist]

214 - cid circuit failure is either the cam sensor or the wiring between that and the pcm. since they are not expensive, I would replace the sensor first.

172 & 176 indicating system lean are typically caused by bad o2 sensors. However, since you say the car runs lean - that suggests a significant vacuum leak somewhere on the intake. In addition to carefully looking for a vacuum leak, I would clean or replace the mafs since a dirty mafs reads less air than what is really there and then everything ends up lean.

335 - dpfe could be the dpfe sensor, or it could be the egr tubing is clogged w/ crap - this is a common problem.

 

[Irish Pride]

The car runs very good aside from the poor gas mileage so i dont think the CID is bad. I think its an older code.

I'll start by cleaning the MAF and see what that does. I'm not too familar with the ATX cars. Where is the EGR and the EGR tubing? Is the tubing something that can be removed and cleaned out pretty easy?

Also, i couldnt get the car to show any codes when trying the KOER test. Is it done just like the other one. Does the car need to be in neutral? Do i have to do the KOEO first then the KOER, or can i just do the KOER whenever?

 

[lowc]

the egr system is on the right back corner of the intake
best way to find out if you have a vacume leak imo is to spray brake cleaner around intake while its running and listen for idle surgeand pay attention to where ur sprayin
and x2 on the dpfe itself and im not sure on the koeo,koer ive always used a scaner

 

[Irish Pride]

I will clean the MAF today and see what it does. Should i use brake cleaner or carb cleaner to check for leaks?

I tried the KOER test 3 more times today and i still cant get it to work. I've followed shophoenix to a tee and nothing. Once i start the engine the check engine light will only come on if i give it a little gas. It wont give any codes.