thanks...

 

Well damn, I'll have to find the discs again to look at it. My tests on this stuff were almost 3 years ago and I am not certain that I am recalling correctly.

 

It is funny. I was talking about the shifting. How many of you guys have heard, seen, experienced it. Some people have said it before too. Feels slow when it is shifting. Has nothing to do with WOT. You all right it should e the same WOT in the gear but when it shifts it is slower. Like there is some time after shifting before it actually goes. When I reset the ECU after her driving it fixed that problem. Anybody with explaination? I tried just floor it after that and did not help. The reset helped right away.

tg

 

I tried it. I floored it(well that is my normal driving). Did not work. After the reset it was a lot faster shifting. Shifting was different(slower) not the WOT.


I keep telling her but she is how she is I guess.

 

It is because the TCM is designed to make shifts smooth and gentle. It does that based on your driving style. If you drive slowly then it will shift slowly for the purpose of making the shifts soft and gentle. If you go back to driving hard it will adjust. It does take longer for the TCM to adjust than the ECU adjusts the engine but it will readjust. The reset just speeds up the process. Another thing you can look into is a grounding kit. There are lots of opinions on that but I did an article for Nissan Sport on the grounding kit for my '04.5 and I can tell you that it did make a difference on the responsiveness of the shift.

 

I've toyed around with both OBD I and II cars logging with http://www.technomotive.com/ on the OBD I and Tunerstein for the II car. Under WOT conditions in either car when cold or hot, the O2 reading is flat i.e. a consistant voltage like .89v. When throttle is anything but WOT, the O2 reading fluctuates greatly. Here is a log, you can see for yourself.

 

Now, I will have to hunt around for a log when the car was cold. I never saved them from the track for more than few days. But, we would run the car cold as ice, and the log would look like the one above, perhaps a coutn or two lower knock being the only difference.

 

i was never too good as far as tuning. but when i did diagnostics o2 sensors generally go from 0-1 volts on the snap-on vantage. normally it would swtich from 0-1 but when forced into a lean condition it would read low voltage but when forced rich it would be higher towards 1 volt.

but i have never tested a sensor when cold...i thought they dont switch and stays at higher voltage until warmed.

 

That is correct.

However at WOT, the o2 sensors are NOT being used for fueling. You can see that by logging your STFT and LTFTs (short term and long term fuel trims). They zero out while in PE mode (which includes WOT).

Also, while the voltage is constant at WOT, the stock o2 sensors are not accurate during WOT. Widebands are.


While logging your o2 sensors, you'll also notice they don't start fluctuating (low to high) until they're warm.

When they're fluctuating..... they're working. That's exactly what they're supposed to do.

 

If you like, I can post hundreds of logs that show this. I did all mine with HP tuners.

 

In "o2 speak" when the voltage bounces back and forth, it's called, "switching."

If the o2's don't do that, you get a DTC that reads "Improper switching bank 1 or 2 sensor 1." That's the front o2 sensor.

 

thanks he was kinda confusing me when he said flutuating i was like...ummm o2 sensors are supposed to do that unless the engine itself it running in a very lean or rich condition.

o2 sensors has to be able to switch and switch in a timely matter.

what i used to do is test o2 sensors with propane or carb cleaner to drive it rich or create a vacuum leak to force it lean. if voltage does not drop then it usually would mean it was a faulty sensor in most cases.

 

I took mine to the track several times.. had a tough time getting upper 13's and 100 mph.

 

what do you think the problem is?

 

The problem is that it takes a great driver in great conditions to run 13's with this car.

Don't expect to be able to on an average run on an average day at the track.