PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

timing issue

Thread Tools
 
Search this Thread
 
Old Apr 21, 2019 | 06:13 PM
  #1  
JHZ28's Avatar
Thread Starter
On The Tree
15 Year Member
iTrader: (3)
 
Joined: May 2006
Posts: 148
Likes: 0
From: NH
Default timing issue

my timing is dropping to 4degrees when letting off the throttle. I believe this is causing a annoying popping through the exhaust the popping is pretty loud. my dfco is turned off I believe. posted latest tune and scan
Attached Files
File Type: hpt
coldstart#2.hpt (247.6 KB, 29 views)
File Type: hpl
gas run.hpl (1.78 MB, 46 views)
Reply
Old Apr 25, 2019 | 05:20 PM
  #2  
JHZ28's Avatar
Thread Starter
On The Tree
15 Year Member
iTrader: (3)
 
Joined: May 2006
Posts: 148
Likes: 0
From: NH
Default

nobody?
Reply
Old Apr 26, 2019 | 12:49 AM
  #3  
ChopperDoc's Avatar
TECH Fanatic
10 Year Member
 
Joined: Oct 2014
Posts: 1,220
Likes: 179
From: Virginia
Default

Really looks like your adaptive spark is pulling it out. On my scanner when you are letting off the throttle, it is registering up to 400-500 rpm error from "desired idle" after about 3-8 seconds depending on your RPM (out of idle routine) so the PCM is pulling spark quick to target it when it resumes idle routines, and that is 14* on your table.

You could add some more spark to the idle tables as well as reduce the adaptive overspeed table a bit in these areas. Legend has it 32* is max torque at idle, so using that, adding to and reducing accordingly on the 2 tables will move your low numbers higher taking the total range down. Say if you push idle spark to say like 22*, then set the overspeed to 10, and I'll bet the lowest it goes is 12 after that. This you will have to experiment with to see what works best. I typically run smaller numbers on the overspeed table for this reason, unless the engine is hanging on too long, which also can be an airflow problem, and usually is.
Reply
Old Apr 26, 2019 | 05:49 PM
  #4  
JHZ28's Avatar
Thread Starter
On The Tree
15 Year Member
iTrader: (3)
 
Joined: May 2006
Posts: 148
Likes: 0
From: NH
Default tune

yes the throttle does hang a little after I let out of the throttle. did u see that in the scan? tried to decreese braf but I believe im already too low as my iac numbers at idle seam to be around 0-30 counts. but car idles pretty good what is your recommendation. im open to all opinions. darthv8r has help me out a bunch he is the reason car idle as well as it does now.
Attached Files
File Type: hpt
coldstart#2.hpt (248.9 KB, 36 views)

Last edited by JHZ28; Apr 26, 2019 at 06:14 PM. Reason: adding stuff
Reply




All times are GMT -5. The time now is 06:22 AM.

story-0
10 Reasons Daily Driving a Swap Project SUCKS! (& 1 Reason to Do It Anyway)

Slideshow: 10 reasons daily-driving a swap project might not be for you. Or is it?

By Michael S. Palmer | 2026-06-17 09:39:05


VIEW MORE
story-1
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-2
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-06-18 10:26:23


VIEW MORE
story-3
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-4
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-5
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-6
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-7
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-8
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-9
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE