Did some checking out of things and it appears the heaters quit. At practically the same time. Now that they read .450mv, my wideband works again so I’m guessing there was a short in one of those two narrow bands and the heaters are dead. I had the wires secured so they wouldn’t burn on the headers. The fuse didn’t blow…
I’m going to replace both tomorrow and verify with a pin out diagram the 02 adapters are correctly wired.
So I got some time in with a set of bosch 13111's.
Seem to have better luck than the GM units. I made some changes, and noticed the most improvement with changing the switchpoints. Took alot of the fuel trim errors out. Car seems to idle better than before. And it switches. If you look at the latest log, it is still kind of crappy at an idle as far as how it switches, though.
I will note that after a drive, when I came back, it did get stuck again. You can see this towards the end of the log.
You will also see that I have some errors showing up across the same airflow mode at different values. So I have more questions now...
- can I reassign the airflow modes to better coincide with these errors to tighten then up without causing something in the rest of the tune to go crazy? Are these airflow modes strictly for 02's?
- I'm guessing the stuck 02 when I came back from my drive is best corrected with yet more proportional? Or is it too much since it got stuck rich this time?
- at what point do I need to take a look at the proportional/integral 02 error tables?
- how close should I shoot to get on the switchpoints? I dont expect to get them exact, but how close to ideal should I expect to get before calling it done?
It kinda looks to me like there is a vacuum leak. Does the engine feel like it's misfiring? See how it stays lean biased at idle and the jaggedness of the voltage traces back toward lean? Up higher it clears up. Be sure there are no vacuum leaks or even exhaust leaks before proceeding with closed loop O2 settings.
I went over the entire system. Resealed the intake, vacuum tested the ac controls in the dash, the vacuum canister and tested the brake booster. If you feel certain, I suppose I could find a smoke machine to test, it couldn’t hurt…
Then again it could be the location of the oxygen sensors. I have longtubes, too. I've applied my settings to your tune. See if it helps at least as a starting point.
You'll notice what seem like high numbers. Look at the multiplier. They're set like that due to numerical limits, but if you do the math it checks out.
Got the chance to run it. It did run better, got to tighten up the switchpoints but it seemed to do better. I made note of the changes for future reference.
After a long drive...it did skew rich again. I think I'm going to pull and read all the plugs, even though I'm not getting any misfires. It also occasionally tends to miss idle and run very slowly for a couple seconds until it recovers, not really at the same time...I'll look into that over the next couple of days.
Otherwise, much better.
Still wondering if moving the airflow modes around is of any benefit. Seems to me moving them around to suit similar ranges of errors within the table would make it maybe a bit smoother, and there are alot of values that arent being used.
Got a chance to really play with it somewhat. I did get it to switch better at idle, and it accelerates and cruises great. It no longer kicks out of CL, it used to stop switching at idle half the time and go OL-fault. But it's still off. I've tried to change the settings one at a time, and I always revert back because it doesn't improve or gets worse.
When it's idling, the RPM's fluctuate between 50 and over 100 RPM at times. You can see this in the fuel trims and the rhythm follows the switching of the 02's. I have tried everything I could to stabilize the idle so I can finish pulling it in, but I can't seem to pinpoint the issue.
Sometimes when decelerating from a higher RPM (clutch in or in N) the engine will go very lean (over 1.7) and the RPM's will fall beyond idle down to 400-500 (it's set a good bit higher than that). The car will stumble and completely lack throttle response, until the 02's correct it back to stoich. This whole scenario lasts 2-3 seconds and usually happens when coming to a stop at an intersection. The higher the RPMs are when they start to fall, the more likely it is that it will do this.
I have pulled in the 02 switch points in several times. They never stay the same.
I did install a IAT breakout harness and installed an IAT in the cold side of the ram air box. Much improved, doesn't heat soak nearly as bad as it used to.
If I put it in OL, it will not do this. I also attempted to stabilize the idle by setting absolute spark with the scanner (made it worse), and by playing with airflow (didn't help).
If I can get this more stable at idle, I think the rest of it will be a snap. I'm sure I'm overlooking something silly.
Cam is unknown. It was installed in the car when I got it. It’s fairly mild. I’m going to say in the ballpark of 218/224 duration.
All the data I have on those injectors is already in the tune. The thumb drive I got with them is at the house so anything else I have I can post later today.
I just stopped to check my MAF. It was a tad lean on the low end but not bad. I’m about to fault the MAF now. Maybe I need to do it differently?
My logs are generally an hour. Combination of city, but mostly highway plus some interstate.
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