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Resident Guinea Wop
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14,542 Posts
Discussion Starter #1
Perhaps unrelated, but ever since I've had my BB tuned PCM in, i've noticed a considerable dip in my idle speed at a light, stop signs, anytime i'm idling in gear, with the brake applied.

Looking at my efilive log files i see a steady 540-560RPM idle, but when the AC compressor kicks on, it will drop to the low to mid 400's causing a brief but noticeable stumble. bbbbbbbbbbbbbb..buuuhblaaaaah...bbbbbbbbbbbbbb :jester:

For why?
 

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Registered
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2,032 Posts
Sounds like either your idle RPM table or idle airflow table needs some work.
 

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HOT AIR BALLOON OWNER
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14,932 Posts
Easy fix.
 

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LAID OUT TIRE FRYER
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1,992 Posts
unhook your battery, then hook it back up after a while. then start the truck and let it learn for a few minutes(it will be rough then start to idle better). then kick the a/c on and it will bog but dont give it gas, just let it learn. it worked for me. the last time i unhooked my battery, i just hooked it up and took off, forgot to let it learn and it started dying on me at lights.
 
M

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Guest
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Sounds like you got a cam in there, bro...wanna race?

I've read about solutions similar to Nick's. I'd give that a shot. Otherwise you can leave the severed head of a horse in Justin's bed.
 

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GMFS Sr. Canadian Member
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4,519 Posts
Pull out that johnson rod and give it a good clean with some brake cleaner, re insert and lube up.
 

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PT.Net Member
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195 Posts
Sounds like you got a cam in there, bro...wanna race?

I've read about solutions similar to Nick's. I'd give that a shot. Otherwise you can leave the severed head of a horse in Justin's bed.
i find myself staring at yer avatar for like 5 mins everytime i read one of yer posts.... :think:
 

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Resident Guinea Wop
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14,542 Posts
Discussion Starter #12
I don't understand the learn part.

This is a freshly tuned PCM, it should of already learned by now, I'm over 50 ign cycles.

I should have to clear anything out :think:
 

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HUNTING
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941 Posts
It sounds like you need to change your adaptive idle air flow while a/c is on...if you need help let me know. I can guide you through it.
 

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Registered
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2,318 Posts
Not sure if you can do this in EFIlive, but in HPT most users do a crank relearn after tuning which helps the vcm learn the new tune.
 

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Resident Guinea Wop
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14,542 Posts
Discussion Starter #15
Not sure if you can do this in EFIlive, but in HPT most users do a crank relearn after tuning which helps the vcm learn the new tune.
lemme try that, EFILive has a CASE learn function
 

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Resident Guinea Wop
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14,542 Posts
Discussion Starter #17
Blackbear's site says you need to do a crank relearn after a tune...
This was a live, on site, in Albany, New York, in person tune.

Not a mail order.

I would have expected Justin to have performed that after he completed the tune on my truck. In person.
 

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GMFS MoPar/Air Force Crew
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5,457 Posts
Did you check out Justin's engine? Sick :drool:
 

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Resident Guinea Wop
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14,542 Posts
Discussion Starter #19
Did you check out Justin's engine? Sick :drool:
It was filthy like the engine bay of a Donk and he told me not to mind the rats nest of wires in the drivers side of his firewall.

:blah:




:crazy:
 
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