Chasing my tail with idle tuning on 5.7 with a lobw buck truck cam

Hi all. I got my Ute tuned quite nicely pre cam swap, I;m struggling a bit with it since the cam. Its a Richard Holdner low buck truck, same as a truck norris.
Can anyone point me in the right direction. It will idle fine for a while then slow and cut out, often cuts out at junctions, it seems to be shifting hard or sometimes will rev to the limiter and not shift at all.
I've been messing with the throttle screw to get IAC down, in the attached tune its maybe a bit low but it doesn't reach zero and still occasionally dies at junctions.

Is the TPS voltage ok at .71-4.32?

what should I be doing next?

I have a wideband on the dash, not currently linked to my mpvi as HP tuners have been sorting an account issue with my pro cable for the last couple of weeks. hopefully soon. It hovers around 1.0 then swings all way way lean and return to center, this repeats every 10 seconds or so.

Any feedback much appreciated!

Attachment 161583Attachment 161584Attachment 161585Attachment 161586

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Originally Posted by Brad-V8locity

what should I be doing next?

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hey mate, let's start with what the vehicle is, what you have done to it etc

cheers

I believe as long as you are under .76v at 0% TPS idle, you are ok, IIRC. What size and brand throttle body? Your IAC counts are too high at idle. Add dynamic airflow [2320.72] to your log channels.

Your Desired Idle airflow is just over 30lb/hr, yet your base airflow number is 103lb/hr. Heres the data from your log applied to the BRAF. Apply this, Wait til the engine is cold, start the engine and try to get it to idle without using the pedal. use the specail functions in the scanner and raise the idle if you have to. Let the engine warm up and collect data until its at operating temp (212F) without using the accelerator pedal. I usually turn the fans off in special functions and let it warm up that way. Then you can get it to 219F, get that data block, and then turn the fans on and let it cool down.

Add Dynamic Airflow to the channels and get a good idle log. Ill try to help with the IAC steps...

Also, a list of mods and what vehicle, like bk2life said.

Thanks for the feedback and yes, fair point I overlooked the useful details.
Its a 2002 Holden VU Ute 5.7 LS1. It has a Monaro intake tube on it and X force catted long tube headers. Just fitted the cam, lifters and trays. Using the stock intake manifold, throttle body, injectors etc.
Attached is an idle log including dynamic airflow. I did it this morning before I saw your reply Horsepowerguru427. I had already brought the BRAF numbers down a bit but not quite what you added to the tune. Once it got to around 210f it wouldn't run any longer without some pedal.Attachment 161601Attachment 161600

That's pretty strange it looks like it just cut right off no reason. It does look like the throttle blade may be open too far. The IAC counts hover in low single digits when up to temp. Need to get them around 40-60 by closing the blade. That will bring the idle trims down. They're "pulling" a bunch of air right now. Getting this closer may fix the problem. Either way it needs to be done first.

I would make the idle spark over/under tables more aggressive especially the underspeed.

Do you have the stock unmodified file? I don't have a 02 Ute file. If you've changed any of the idle PIDs that will aggravate the situation.

Next thing is your VE. You're in speed density so you're obviously running off the VE. The way you have it setup you're idling in a trough. so if it goes to dip in idle speed there isn't enough underspeed spark to try and hockey puck it back up and then you end up in the lower 400 rpm column which is considerably risher than the 800 rpm column. So essentially it's choking itself out on fuel.

The 400 column needs to be numerically lower than the 800 column. Especially right there were you're idling.

Attachment 161602

I think you get those 3 sorted you should be pretty good.

PS you're logging way too many pids. Need to get rid of 75% of them.

That was great advice edcmat-i1.
It now idles like a lumpy honda generator, however, it dies as soon as I put it in gear. I had a bit of a mess about but ended up giving it a bit of throttle to drive home from work.
If I slow to a junction slowly it seems ok, if I slow quickly, itll cut out. also, the revs seem to hang a little.
This may or may not be related but the trans is slipping 2-3rd a bit now.

I guess next I incorporate the maf from the "idle to hot 2" log into the base running airflow. Fail the MAF to dial in the VE table again. A bit more in the in gear base running table to keep it going better?

Thankyou again for the advice, its making my trips to and from work much easier!