EFI live = Incomplete tuning package!!!!

Hi NASA,

Don't dispair, it could be worse...

Here some idle tuning info (I'm not sure if you've seen this):
Idle Tuning:
showthread.php?t=4661 <-- idle tuning tutorial by SSpdDmon
showthread.php?t=149
showthread.php?t=5866
showthread.php?p=86553 post #17

Cheers
Joe
:)

thanks again joe

I'm going to look these over

:cheers:

My trick for calibrating an installed wideband on a car with a cable actuated TB:

In park, run the engine up close to its rev limiter.
Turn off the key.
At the same time, open up the throttle 100%.

As the engine decelerates, it will pump fresh air into the exhaust system. Enough to purge exhaust gases from the O2 sensor area.

You might be able to do this on an ETC car by using bidirectional controls to cut fuel? Or by setting the RPM re-enable after overspeed fuel cut to 0 RPM in the tune.

Quote:

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Originally Posted by PSWired

My trick for calibrating an installed wideband on a car with a cable actuated TB:

In park, run the engine up close to its rev limiter.
Turn off the key.
At the same time, open up the throttle 100%.

As the engine decelerates, it will pump fresh air into the exhaust system. Enough to purge exhaust gases from the O2 sensor area.

You might be able to do this on an ETC car by using bidirectional controls to cut fuel? Or by setting the RPM re-enable after overspeed fuel cut to 0 RPM in the tune.

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Although this will get you close, it's still not as good as a free air calibration with the O2 sensor outside of the exhaust. I've seen over a 1/2 point of difference in AFR readings using this method of calibration. So, I'd rather take 5 minutes to unscrew the sensor from the exhaust and calibrate it...

SS

Your write up on idle tuning is Great!

I'm trying to work around being able to increase my learned idle airflow time on my 97 PMC. But things are making much more sense this time.

Last night I tried to log some data, which I did, but I couldn't clear my LTFT and STFT, as the option wasn't highlighted in my option menu.

Sure is great to get her back on the road, even if the drivability isn't good. When she's under part throttle, the AFR is 13.5. IT seemed to be better wikth less bucking when it was cool. AS it warmed up, it was much worse.

I'm still reading (re reading and re reading) through your posts and digesting... but thanks for your time writing these up.

So, not that I'm there yet so what, does the road runner add to the picture?

Quote:

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Originally Posted by NASABlue

SS

Your write up on idle tuning is Great!

I'm trying to work around being able to increase my learned idle airflow time on my 97 PMC. But things are making much more sense this time.

Last night I tried to log some data, which I did, but I couldn't clear my LTFT and STFT, as the option wasn't highlighted in my option menu.

Sure is great to get her back on the road, even if the drivability isn't good. When she's under part throttle, the AFR is 13.5. IT seemed to be better wikth less bucking when it was cool. AS it warmed up, it was much worse.

I'm still reading (re reading and re reading) through your posts and digesting... but thanks for your time writing these up.

So, not that I'm there yet so what, does the road runner add to the picture?

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Thanks....back when I had time to put some text on this site, I figured it was worth sharing - so I did. Been a lot busier lately. One thing you'll find is that reducing timing or richening the AFR can help with the drive-ability. Also, getting the airflow right (TC and TF) is important. If you're running closed loop, you may need to adjust the switching points for low speed driving to help keep the bucking at bay. I guess working with a '97 is a little more difficult with there being fewer options for adjustment. The best I can say at this point is good luck and give it your best shot. Make manageable changes and keep what works. =)