Where's a good starting point for cold idle surging

[edcmat-l1]

How do the LTFTs contribute to the issue? Also, why did you have me turn my fuel trims off? (For my future knowledge)
I'm not being hard to get along with, I truly want to understand what I'm doing. I feel like I'm blindly making changes and I don't know why.

I didn't have you turn you fuel trims off. I had you turn your LONG TERM IDLE TRIMS OFF. You need to turn your LONG TERM FUEL TRIMS OFF AS WELL. If your LT FUEL TRIMS are positive when you start it up, then they're going to ADD to your ueling, causing an overly rich condition.

As for the idle trims, I've found that most all of them run better, and have better idle control without them. Long term anything will tend to embed issues you don't want them to. Happens with fuel trims, and idle trims both.

[99LS1SS]

I was under the assumption that when I reset fuel trims that reset the LTFTs also.

*edit* Thank you for the explanation. I sincerely appreciate your help with this car!

[MMGT1]

It will reset the long as well, but instantly the long starts "learning" again from Short input.

[99LS1SS]

It will reset the long as well, but instantly the long starts "learning" again from Short input.

I was not aware of that. Thank you.

[99LS1SS]

Here's the tune I'm getting ready to try and start the car with. Should I change anything before I try?

One other question. If my LTFTs are enabled while I'm trying to log my VE to fix it, am I just wasting my time? If so my VE could be way off because I haven't disabled my LTFTs until just now. If the answer is yes then I need to redo my VE because I'm sure it is screwed up.

[edcmat-l1]

Here's the tune I'm getting ready to try and start the car with. Should I change anything before I try?

One other question. If my LTFTs are enabled while I'm trying to log my VE to fix it, am I just wasting my time? If so my VE could be way off because I haven't disabled my LTFTs until just now. If the answer is yes then I need to redo my VE because I'm sure it is screwed up.

Exactly my point. Turn off the long term trims. Reset your fuel trims using the scanner. Go back over your VE and MAF. Then start on your OLEQ table again.

[MMGT1]

If long was active, you need to use a PID that will give you results of both LTFT+STFT. Here is where you will find mixed reviews. Some, like edcmat there that will dissable long and use short only. I use the LT+ST but I do see where the ST only is a dam good way to do it. Short is very quick, up to the second response and makes things pretty easy to do. Always keep in mind as well, the trims you see are a reaction to an event, so hitting the cells a little in your fueling table right before the event is good practice and will smooth things out a lot faster.

[MMGT1]

You guys have probably already covered this, but in VE use the smoth button, a lot...lol That sucker should be smooth as all hell when yo are done. When you smooth, trims are going to go insane, but keep on it and it will shock the sht out of you how nice it will look in the end.

[99LS1SS]

Exactly my point. Turn off the long term trims. Reset your fuel trims using the scanner. Go back over your VE and MAF. Then start on your OLEQ table again.

Should I set my after enrichment tables back closer to stock while I'm redoing my VE?

[edcmat-l1]

You guys have probably already covered this, but in VE use the smoth button, a lot...lol That sucker should be smooth as all hell when yo are done. When you smooth, trims are going to go insane, but keep on it and it will shock the sht out of you how nice it will look in the end.

Search my posts on smoothing. It is overrated.

[edcmat-l1]

Should I set my after enrichment tables back closer to stock while I'm redoing my VE?

Just leave them for now. Once you've got a little temp in it, they're out of the picture anyways. Get your airflow tables dialed in, and your STFTs in line. Then go back and do your OLEQ and afterstart enrichment tables, if needed.

[MMGT1]

I am kinda stagnant on the issue of smoothing I know. I have seen the posts from you and I must say you are one of the best Ive seen here. I just can't leave physics out of this. In my mind there is a ve table that is very, very smooth that will result in excellent delivery every time. When I see dips and peaks, I have to figure it out...lol I cannot figure out how dips in a ve table are actually possible. I have myself convinced that if there are dips, then it is the previous cell that is causing it. Splitting the difference between the event and the previous cell I have ended up with a very smooth table in the ones Ive done. And no, nowhere near the #'s you've put out by the way...hahahaha I think you are getting at the fact that you see no increase in power through smoothing and feel it is not necessary and a waste of time?

[99LS1SS]

I just retuned my VE and MAF. My MAF was still pretty close but my VE was between -4 to +10% off in some areas. If I understand how to read the VE table, it was rich at low RPMs, which makes sense given my trouble.

Here's my "new" starting point tune with my new MAF and VE calibrations. I need to wait for the car to cool back off before I can see if it worked.

[99LS1SS]

How cool should I let the car get before I crank it? Right now the ECT is 115 and it's been sitting for 2 hours with the hood up. It's 50 degrees right now so I don't know how long it will take to cool off totally.

[99LS1SS]

I let it get down to 104 ECT. Here's the startup log. It is still surging.

[99LS1SS]

*edit* dumb question

[99LS1SS]

I've got to take this car back today. He's getting antsy. The surging is a little better than it was. Do I need to set the adaptive idle airflow back as well as the LTFTs?

[edcmat-l1]

You're still too rich. If you look at your log, it comes out of the surge just when it goes from 11.3ish:1, to right about 15:1. All the while, your commanded is stoich.

The leading cause of surge is too much fuel. Always. always, always. Get the fuel out, the suge will stop.

[99LS1SS]

This car is absolutely whipping me. It seems like nothing that I do fixes the surging.

[99LS1SS]

edcmat-l1, how much after start enrichment fuel can I safely take out? Because, if that is causing the surging, then I'd be willing to 0 it out just to see if it helps.