Swap - 5.3 -4l80e-HANGING IDLE AFTER REV

Im in need of some help, i have loaded the file, its 5.3-4l80e. The 4l80e trans was seg swapped in , and not sure if that is where it went wrong or what. this is a buddys car and he had done by local tuner the tuner seams to have motor dialed in pretty good. but the trans shifts weird. like it keeps locking and unlocking. but the big issue is the idle not sure if related, but in every gear if the rpms go up they hang there for a good 5 to 10 seconds before dropping back down, and it comes down pretty slow when it does. Trying to figure out what is going on, looked at cable and throttle body itself, tried different tps and iac, really looking like its in tune somewhere, might not be looking in right spot. i know some people on here can probably open file and go right to it. if you can help me out would be greatly appreciated.

its 5.3 - 4l80e ( seg swap ) custom grind cam, fast intake, cable throttle , 411 ecm

let me know if you need any other info,

thanks

Gots you a log to go with that?

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Originally Posted by SiriusC1024

Gots you a log to go with that?

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sorry i dont

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Originally Posted by SiriusC1024

Gots you a log to go with that?

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it does it in any gear, even while driving it hangs, and in neutral and park also. dont matter if you raise rpm to 2k or 3k or 4k it hangs for a couple seconds and drops slowly

There are a few things that can cause that. I do see plenty of flaws in the tune, but a log is needed.

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Originally Posted by newbie1987

it does it in any gear, even while driving it hangs, and in neutral and park also. dont matter if you raise rpm to 2k or 3k or 4k it hangs for a couple seconds and drops slowly

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Instead of explaining go run a data log and post it.

having trouble with his mpvi2 , think it got shorted out off a ebay bench harness. was hoping it was something that could be found just by looking, maybe not tho. what are some flaws you see? anything that might affect that? i thought about throttle cracker but they way i understand how that works is pretty much threw iac correct? so we tried changed and unplugged iac so it wouldnt control it and did same.
i wish i could run a log but not a option atm
but if there are any issues with file , or something weird that might cause that please let me know.
guy that did it wants more money to run log or anything and would like to just avoid him. so any help by looking, ordering a mpvi3 here shortly and hope to try some things out.

Um. I hate the spark and VE. I especially hate the lack of torque management. High RPM Disable 2000rpm cuz reasons. Not saying these are the problem, but if that shop does this kind of work...

Really need to see the log. People guessing is what got you into this situation.

Based on the mods and the fact it does it with the IAC unplugged leads one to believe it is not toon related and more likely a vacuum leak. Without looking at any data of it running it's just a guess.

Never heard of an interface being shorted out. That's a new one for me.

That being said, the toon is pretty ugly. Injector data can't be right so everything is else is wrong.

When the FAST manifold was installed, were the valley cover bolts replaced with button heads? OR did they bolt the intake on with the stock valley cover bolts in place?

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Originally Posted by edcmat-l1

Based on the mods and the fact it does it with the IAC unplugged leads one to believe it is not toon related and more likely a vacuum leak. Without looking at any data of it running it's just a guess.

Never heard of an interface being shorted out. That's a new one for me.

That being said, the toon is pretty ugly. Injector data can't be right so everything is else is wrong.

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yeah it clicked loud when it got plugged in almost like a pop , and now it just says no power detected no matter what.

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Originally Posted by edcmat-l1

When the FAST manifold was installed, were the valley cover bolts replaced with button heads? OR did they bolt the intake on with the stock valley cover bolts in place?

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valley cover was also replaced with ict billet new gasket and bolts

Quote:

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Originally Posted by edcmat-l1

Based on the mods and the fact it does it with the IAC unplugged leads one to believe it is not toon related and more likely a vacuum leak. Without looking at any data of it running it's just a guess.

Never heard of an interface being shorted out. That's a new one for me.

That being said, the toon is pretty ugly. Injector data can't be right so everything is else is wrong.

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We did just try it with a random ecm that was just a vats deleted ecm laying around , and its all stock so cant use for long, but just seeing if it was on motor or in tune , and the stock ecm revs fine, and returns to idle fine. so i know its in his tune somewhere.

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Originally Posted by newbie1987

We did just try it with a random ecm that was just a vats deleted ecm laying around , and its all stock so cant use for long, but just seeing if it was on motor or in tune , and the stock ecm revs fine, and returns to idle fine. so i know its in his tune somewhere.

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Then do a data log with the stock PCM and one with the modified PCM. Then use your compare feature and compare your modified tune to a stock tune file and try to figure out what tables are goobered up.

WE are all just guessing without a log.

My guess is the TPS isn't returning to 0%. common with aftermarket throttle bodies and easy to fix.

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Originally Posted by Alvin

WE are all just guessing without a log.

My guess is the TPS isn't returning to 0%. common with aftermarket throttle bodies and easy to fix.

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figured it out, must have been something that happend during flash, loaded same tune to the other ecm and worked fine.