Extremely Lean Decel..Not DFCO

[nikon1999]

Anyone that could please help me with this it would be greatly appreciated. I'm at a loss, i will attach the config i used to log and my log/current tune. Basically im getting there on the idle tuning it seems, i have everything turned off cat, dfco, cl, so im working right on the ve table. I cleared out my spark over/under tables so that is a constant so i know that isn't causing surging. I've updated my injector data to what i think is correct from searching through 100's of posts on here.
Now when im coasting to a stop the car shoots up to 16-20:1 afr, idles real bad and wants to die, then like a switch it pops to 11:1 afr. Looking at the tune the timing is pretty constant so i don't think its switching from a drive to idle table. The injectors are firing the same msec when its lean and when its rich. i don't know
Frames to reference on the log for example, 450, 1850, 2400.

Any help would be much appreciated.
Thanks

[69lt1bird]

What are the details of your engine? size, cam, which injectors, anything else you want to share.

[nikon1999]

sorry forgot all that stuff!

stock bottom end, edelbrock 205 heads, 236/236 .601/.601 112+2 cam, vengeance ported fast 90/90. kooks stepped headers. lucas 42# injectors.

[69lt1bird]

Some place on here is a PID from Russ K called RAF, running air flow. Your numbers look low in the Base Running Airflow table so maybe is it struggling for air when you close the blade. Also your idle timing is pretty low. The Idle Spark Advance table is what you should use for that adjustment.

[nikon1999]

appreciate the response. I've logged using the raf pid numerous times and these are the numbers its calling for roughly. Also in terms of timing, playing with the bi directional controls this netted me the best map reading. I get conflicting answers on spark, some tell me between 15-20 is the normal others are 24-28. I don't see how the spark could be causing this though? cause its holding at a constant value not shooting up or anything to cause the lean spot.

[69lt1bird]

I would give it somemore timing at idle, have you wideband tuned the ve table yet? I am seeing 12.2:1 or so in your tune log. That needs to get leaned out also. way too rich is that is accurate.

[69lt1bird]

Read thru this link
http://www.hptuners.com/forum/showth...8776#post78776

[nikon1999]

appreciate the help. But i've gone through those steps numerous time. To no avail. The ve has been tuned. I see 12.2 in some cells, and then in the same cell it'll be 16.x further down the log. How do i tune for that? Its a 1 bar sd tune so no secondary ve anymore. So i don't see where the two values are coming from

[Bill@HPTuners]

I think one of the main problems is that your maf codes are wrong, set them to no mil light rather than no error reported as this is confusing the crap out of the pcm. See if that helps to fix or alleviate some of your issues.

[slow67]

Actually uncheck the SES enable and set it to MIM om First error

[nikon1999]

i didn't realize that those settings still applied if you were running a 1 bar sd os. I unchecked the ses enable and set it to no mil on all three codes, will post back tomorrow

[nikon1999]

i unchecked the ses enable box and turned all three codes to no mil light per request.

On initial start up it wouldn't stay running, took about three time cranking over. Ran like garbage until about 150 degrees then like a switch it smoothed out? Smoother than it has EVER been! Now what i need to figure out is at the same time i was playing with the RTT and added all the spark values back into my over/under tables. But i never executed the operation? just made changes on the flash values

Still having a big problem with it going extremely lean coasting to a stop, then once again like a switch it'll go from a 20:1 afr to 11:1 afr. Sometimes coasting to a stop though its fine? I'll attach a log from last night, it's long, but i wanted to see how my ve table was as well.

The lean spike you can see at frame 8800, frame 11000 it stayed lean even getting into the throttle, didn't want to move? It happens through out the log but those are just two points i spotted quick.

Any ideas on the fueling?

[69lt1bird]

It may be a bi-product of the issue but your MAP goes nuts just before the lean surging starts. At one point it is the throttle is at 1% but you have 77 kPa on the MAP sensors reading.

[nikon1999]

69lt1bird -
when i had to install the map in my fast intake you have to rtv it to keep it in place. Perhaps there isn't a good seal there? wonder why it would be so dramatic now though, have had the intake for 2 years.

How do you test if a map sensor is bad? cause the car idles great now and drives great.

[muayyadf1]

So what was the issue?

I have the same thing here also after I installed green tops and used gregs data.