Nice work Mitch. Keep us posted with the results after more seat time. Also nice trap speed.

I'm sure my tune is locked. I may just have to deal with it until I get a retune, or put up with the CEL.

who tuned your car? if you have a good relationship with him he could probably just email you the updated map with O2 sensors removed

You could try just the cold timing tables. The O2s were to just get it to idle and drive with both banks at the target afr. I found that if you keep the O2 plugged in one bank will always run richer than the other under closed loop.

soon as I get my new ft O2 sensor I'll have to do some more closed loop logging. I don't recall one being richer than the other.

are we sure the ECU doesn't use the post cat O2s for anything?

Vince at R/T Tuning.

I'll let Mitch do some more testing to be sure this is the fix before I call R/T Tuning to see if they can patch my tune.

So far so good, the lean idle has more or less stopped. But a new quirk has started which I think may be related to my changes. I been around these tuning programs long enough to realize that table names dont always mean what they suggest they should mean.

For example this car switches to that "COLD" fueling table at idle under some conditions (causing the lean spikes while idling). I would assume that that fueling table might actually not so much be a cold table as it is some sort of emissions modified table on the car. Either way changing the cold table with the main table values fixed pretty much everything. However now on hot starts it will take a second or more to crank up which also means that this car may be using this as a fueling table for starting.

My solution to this is take the cranking region of the table and return it to where it was before and see if that gives me the best of two worlds.

Either way this engine is still running strong and happy at 12-13PSI of boost.

Nice work Mitch...Keep up posted!

Since my tuner is a sponsor here I'm totally just going to have him read this thread and see if he thinks it's worth tweaking anything during my next tuning session.

Oh...and you are running 13psi? What power level is that?

Thanks, I just want to get this figured out and if others can benefit then im glad.

No idea what power level that is, its enough to run 120mph in the 1/4. I believe before all this started I ran 110mph last year. I am going to try and get it on a dyno for a few baseline pulls just to have a number.

It is at the limit of the fuel I have available up here without running any sort of additive. I did sacrifice some tq for some hp in my tuning. I can feel that much, but the hp makes it well worth the loss in lower end tq.

Also when I say 13PSi that is my absolute peak, it settles around 12.5ish most of the time with 0 knock. Keep in mind we have 94 octane up here as well.

Not that it really matters but when I had my car tuned, it was a whole new tune and not from the modifying the base map. Maybe that is why I do not have any problems with idle.

all the base maps are locked. all of us have custom tunes from scratch

Then I have no idea. Maybe the cold fuel table was missed by other tuners.

I'm definitely clueless. just hoping somebody finds a fix. mine is starting to idle worse. I think it might be that O2 sensor going out. replacement should be here Wednesday

I logged my idle and was wonder what is a good third party site that allows me to share this file.

If you already have an account, Dropbox makes it really easy to share a file or folder via http link.

Dropbox is an excellent choice. Use it for online DJing and have access to unlimited music