Code Question! (I did a search already)

[MusPuppis]

Ok, first off, thanks to Jrichker for his posts on how to pull codes with the CE light. Your a life saver.

Anyway, I went out this morning and did the KOEO and KOER test and got a couple codes that I then looked up (troublecodes.net). I wanted to run em by folks to make sure I got the right idea as to their meaning. Anyone who's familiar with codes and such please let me know if I'm on or off-base. Thanks guys.

(Note: the engine was allowed to get good and warm before performing the tests. Approx. 15 minutes of neighborhood driving.)

KOEO-

Hard Codes
552 - "AIRB Selenoid Failure"
552 - "AIRD Selenoid Failure"

These are in relation to the smog system sensors I removed. I was told they'd throw a hard code but there would be no other ill-effects. I would have kept the smog system but the guy I got the engine from had JB Welded the bolt holes on the heads shut, lol.

Memory
334 - "EVP Sensor was/is high - EVR"

Not real sure on this one. My EVR is missing the little plastic cap and sponge filter which as I understand doesnt effect the sensors operation it just opens up a chance to suck in debri or something. Im replacing it, just havent had the time yet. However, with the back off a friend of mine stuck his finger on the line in the rear of the sensor causing the engine to drop down and run like ass for a few seconds then catch when he removed his damn finger. I'm assuming this memory code is in relation to that incident.

KOER-

311 - "AIR System not working - Single, right or rear HO2S - Air Injection"

The 311 code is the one Im concerned with. HO2S would be my o2 sensor wouldnt it? I guess this would indicate its failed/ing. However, could a cat in the latter stages of life cause the o2 to function improperly? My cats about 115k old and the old engine ran very poorly for a while and I suspect it could have shot some oil into it. The truck also sat for over a year without ever being started. The truck is also running very rich before it gets warmed up which isnt good for them either.


Also, if your wondering why I'm pulling the codes in the first place its because my trucks running a little crappy. When its first started up it runs VERY rich. It throws a pretty hefty amount of brownish, gassy smelling smoke and if you rev the engine any and let off it'll flood and stumble pretty badly. Also if you pull the plugs after running it but not allowing it to fully warm up their practically swimming in gas. Once it gets heated up though it starts running a little lean. The plugs show signs of that anyway.

Assuming the 311 is my o2, could an o2 cause the problems Im experiencing?

Anyway, Sorry this was so long. Im a long winded bastard. Thanks folks,

 

[Michael Yount]

According to Probst' book on the Ford EEC injection:

311 - "Thermactor (AIR) air system inoperative (right side)"

334 - "EGR closed valve voltage higher than expected"

552 - "Air management 1 AM1 (AIRB) circuit failure"

The failure in the egr circuit can cause drivability issues - especially if it's allowing exhaust gas to enter when it's not supposed to - like at idle.

How old are your O2 sensors? If they've got more than 30-40K on them, and you're gonna keep this for a while, you ought to get new ones in there anyway. Those sensors degrade in performance from day 1, and ought to be considered a consumable on cars with them. They ought to be changed every 50K. Your vehicle has no O2 sensor AFTER the cat, so it's sensing exhuast stream un-treated by the cat. Unless the cat is clogged negatively impacting back pressure in the exhaust system, cat degradation won't be picked up by the O2 sensor - it's before the cat. Newer cars have sensors before and after the cat to determine just that - if the cat is still functioning as it should.

 

[HISSIN50]

on the EGR, check the lash of the seated valve. as the EGR valve wears, the valve position senser does not know the valve is wearing and has a 'new' position that it is closed at. and so it thinks the valve is open a little, when it is closed.

good luck bud.

 

[MusPuppis]

k, those codes differ slightly from that website said.

The o2 sensor is pretty old. 50k+ I would assume, so I'll go ahead and replace it.

As to the EGR error, would this be in the EVR or the EGR sensor itself?

Thanks, =]

 

[jrichker]

Code 34 Or 334 - EGR voltage above closed limit - Failed sensor, carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. If it leaks, there is carbon stuck on the pintle valve seat, replace the EGR valve ($85-$95).

If the blow by test passes, and you have replaced the sensor, then you have electrical ground problems. Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohm. Next check the resistance between the black/white wire and the negative battery post. It should be less than 1 ohm.

Note that all resistance tests must be done with power off. Measuring resistance with a circuit powered on will give false readings and possibly damage the meter.

This will affect idle quality by diluting the intake air charge

 

[MusPuppis]

Ahh ok, excellent.

I'll pull the EGR valve off and clean it up and see what I can accomplish.

This could be a potential cause of my problem then? I dont actually have idle issues exactly. It just idles and runs poorly until it gets heated up, then its pretty smooth.

Welp, I'm gonna go ahead and pull the EGR off and clean it up, I'll get back to everyone when I have it tested, =]

 

[cjones]

changing the O2 sensor for a code 311 - "AIR System not working - Single, right or rear HO2S - Air Injection" won't stop the code.

during the KOER, the computer switches the AIR to upstream to check the AIR solenoids, since your AIR is disconnected the computer will not see a full lean signal from the O2.

 

[MusPuppis]

This is in relation to checking the EGR as suggested.

I pulled the valve off the plate and there were two holes. The top has the valve itself in it and the bottom has nothing. I sprayed it with some carb cleaner then put a little Simple Green in the open hole and positioned it so it would sit a little to break up any deposits (hopefully anyway). I dried it all off as best as possible and tried to blow air through the valve side. Well, I wasnt able to make any seal with my lips so I had no way to tell if the air I felt was from me or the valve so I got some extra hose I had lieing around and cut it as straight and flat as possible. I used the hose to straddle the valve where it protrudes and put some pressure on it to make a decent seal, then blew like a madman. All that gained me was a head rush followed by a headache. No air seems to blow through. When i put enough pressure on the hose to make any type of effective seal I cant push any air through.

This would mean the EGR valve is good correct? I just want to make sure I did the test correctly so i know I'm not missing anything.

Assuming I did it correctly, I'll put the EGR valve back on the car and pull the terminals off the battery so the computer resets, then drive around a while then pull the codes again to see if that fixed that error. If not I'll check the resistences as suggested.

Once thats taken care of I'll replace the 02 sensor, clear the codes and run them again. Even if the code crops back up since the Smog system is disabled maybe the new o2 will none-the-less alleviate my problem.

 

[Michael Yount]

You keep refering to the sensor in the singular. I presume there are a pair - I'd renew both. If they're they age you say, they could both use it. Do those before the battery-disconnect-computer-clearing operation too.

 

[MusPuppis]

I only have one o2 in my truck. The pipes come down from the flanges and lay on top of one another and go into the cat, which sits maybe a foot behind the engine. The o2 sits in a little bridge between the two pipes. This exhuast is horrible though. The pipes are really short, so basicly as soon as the gasses exit the stock manifolds, they get slammed into the cat. I have a pair of headers sitting in my garage, just dont have the cash to get the rest of the exhuast.