Just got the headers installed and everything running again... made a short data log if someone could take a look over it and see if anything is out of the ordinary before I start tuning. Thanks.

http://www.mediafire.com/?mmzjdymw1lb

 

Your left o2 sensor is smoked or you have a harness problem over there. I would drive the car a bit just to get the headers hot a few times, and then change the sensors, I assume these are new coated headers. After that I would log again and see if the trims are the same. For some reason your car seems to be adding a lot of fuel in the trims, you either have a vacuum leak somewhere, or a header leak on the right side. I would say likely a header leak of some sort because of how your iac counts are.

But it is also highly possible that the o2 sensor on the right is also damaged thats why i recommend changing them after a few heat cycles.

 

Left O2 not working... stuck in the range 444-502mV. As a result, it seams to be limiting long term corrections to Cell 16, 17 and 18.

Battery voltage is low, in the range of 12.0-12.7V

IAT appears to be heat soaked, with air temps up to 132.8*F

Around record 5898, the right O2 drops below 100mV and stays there, while the left O2 is stuck in the high 400's. As a result, the PCM disables the learning, and defaults to 128 for long term and short term fuel trims. Up toward the middle of the log, the right O2 sensor gets stuck above 800/900mV.

Something is screwed up with the O2 sensors. Its not an open loop tune, is it?

What scan software are you using? Its logging at 16 frames per sec... unusually high.

There's no knock retard, but then its barely being driven. IAT, MAP afGPS, TPS look OK. One place where it shows 47* spark advance, which is sort of high.

 

47* spark advance is probably egr timing table that he hasnt zeroed out yet.

Its not an open loop tune or it would never try to learn ever at all. Just hang on 128/128 forever.

His iat value isn't terribly unreasonable given what its been like outside lately. Hot blacktop and not being driven too quickly, especially if he has a cai that is close to the ground like most are below the stock airbox location. Pretty easy to verify if its working correctly just let the car cool completely over night and note the temp of the water and the iat are reporting before starting the car they should agree pretty closely.

If he has installed coated headers, when the coating "cures" on obd2 stuff it will report slow repsonse from the o2 sensors and set a dtc. Seems consistant with whats happening here, just nothing to set a dtc.

He seems to be using freescan to log.

For the op: what kind of o2 extensions are you using, did you splice it or buy something?

 

Wow, thanks for all the responses guys.

First of all, the headers are uncoated. The o2 sensors are stock (136k on them, I know I know) and I made the harnesses. I cut and soldered each connection, and heatshrink wrapped each joint, then put the whole harness in a plastic loom. You don't think a few cycles of open headers melted the solder joints do you? Either way, shouldn't it throw a code for o2 sensors? I'm only getting EGR, a "CCP" code (DTC 26... air pump?) and a TCC code.

I do have a minor leak I believe around the throttle body/rubber elbow just because it's a crappy torn elbow, and I need to find the funds for a cold air... all of the other leaks I believe I've taken care of. My passenger valve cover is leaking a bit I think, because that side is burning oil (I assume, smells like it and it's white smoke) constantly.

Battery is less than two years old, and alternator is putting out, but I'm not sure what amperage... I'll be sure to test it at work tomorrow.

Also, my max spark retard tables were zeroed out because I had an exhaust leak giving me false knock bumping timing some odd 26* at WOT. Headers took care of that problem.

After I got this log, I set my EGR enable max RPM to 6000 and min to 100 RPM, reset the codes and flashed the PCM... the light and DTCs still came back. I also put my max retard tables at 10*, I can't remember what stock setting is.

The IAT very well could be heat soaked. Black car, hot Arkansas sun, parked in the daylight all day. Or, it could be damaged... crossed plugwires caused a few rough backfires out the TB so that might have hurt it.

Can't properly judge coolant temp, because the gauge doesn't seem to be working properly, it never climbs more than 1/4" at all. Broke the sensor and replaced it, so I don't know what's up with that.

 

If you reworked the wiring on the O2's harness (not the car's harness) you could have ruined the sensors. They should not be altered. A pre-made extension is better.

 

I've read numerous accounts of people extending their own (in effort to save an otherwise wasted $40) and it being just fine. I don't see how (though I don't doubt you ) merely extending the wiring could foul a sensor. My better guess is that they were already out (like I said, 136k on stock sensors) or near it. Does OBDI not normally trip a DTC for abnormally high/low voltages to the sensors?


[edit] Any idea if 3.4l o2 sensors have the same 4pin flat connector? If so, I know where there's one being parted out that I could take the pigtails from and make my own extensions for new sensors... would that be a better option?

 

if your going to try it yourself. you need to do it to the cars portion of the wire (Wires going from car to connector, not from o2 sensor to the connector). you cant cut and solder the wires on the o2 sensor becuase it gets sample air threw them to compare the air inside the pipe to the atmosphere. you basicy take away its refrence point when you do that.

 

As seemingly inaccurate as that explanation is, I went ahead and got a set of extensions for $35 and I'll by buying new O2 sensors soon. Does it seem they're both bad from the logs? Or just one?

 

Both o2's are bad, the signal is anyway. Fix the tear on your tb elbow and all the other little issues you mentioned earlier like the leaky valve cover.

To get your ses light to quit coming on for egr turn off the trouble code for it. It doesnt matter when it activates if your pcm does the test for it its going to trip the code. So you have to go and turn the flag off for that test.

Don't judge your colant temps by the gauge in the dash. Your pcm doesnt use that one anyways. It uses one stuck in the water pump to determine coolant temp. Compare the reading from freescan for coolant temp to the iat reported when the car has cooled over night then you know exactly where you stand.

 

"If you are replacing the O2 Sensor with a universal replacement sensor, you'll have to splice the factory connector plug onto the new sensor. Or if you've order a sensor kit which comes with connectors, you'll have to install the connectors which come with the kit onto the new sensor wires. DO NOT solder the connectors onto the wires. They must be crimped on for the O2 sensor to work correctly. For the sensor to work correctly, it must draw clean air down to the sensor through the air gaps in the stranded wire. If you solder the wires, the solder will fill the air gaps in the wire and the sensor will not work correctly."

http://www.clarks-garage.com/shop-manual/fuel-18.htm

 

That explanation makes much more sense, thanks for clearing it up . I had no idea that was even part of it's function.

As for both o2's being bad, what's the standard voltage it should be at? Obviously being stuck at .4xx volts on the left is a surefire sign, but what about the other one? It fluctuates a bit, and is much higher, what should it be reading?

I'm going to get a new left sensor today (I assume that's left as in bank 1, driver's side?) and the extensions should be here within a day or two. Valve cover leak was taken care of, the gasket wasn't inside the lip like it should have been. The TB elbow I'm going to try to deal with until after vacation and I can get a new one. Might try to put some clear silicone around the tears, let it harden, then try to stretch it over the TB.

Thanks for clearing up the EGR issue, I thought simply tuning it not to come on would deal with the SES light. Coolant temps only peak at 85*C, which isn't abnormally high, but then again it wasn't run very long, and I'm only running water in it right now, no antifreeze.

 

In a shop you cant just throw parts at a customers car (o2 sensor) you need to verify that that part is actually at fault. When ever your about to order somehting, Ask your self, how can I prove that this is actually the problem?. If you dont have the proper equiptment to check it (scope) then the best thing you can do is swap front sensors side to side, if the problem follows to the right bank - then you know you have a bad sensor/ bad sensor wiring after the connector (wich is what a new sensor comes with). That way you can be 100% posaitve your not wasting money on a new sensor you dont need. If the problem stays on the left bank then you dont need to order a sensor, you need to do some tests!

 

After the car is in closed loop (warmed up and run for 200sec or so), the o2's should bounce back and forth rapidly from about 150mv to 950mv or so. If you log with tts datamaster you can make it show this on a graph it will look almost solid on a 15 min or so log. It does this because your car is set to average air fuel ratio it bounces back and forth from rich to lean.

 

Well it's been reccomended to change O2 sensors with a header install (coated or noncoated alike) by a few people, plus they have 136k on them, and I fubar'd the wiring in splicing apparently, so I figure I'll go ahead and replace them anyway.