PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

LS1 Conversion With Issue of Computer Pulling Timing after Running for a while!

Thread Tools
 
Search this Thread
 
Old Dec 14, 2009 | 05:22 PM
  #1  
BoostedLQ9SS's Avatar
Thread Starter
On The Tree
iTrader: (11)
 
Joined: Nov 2008
Posts: 161
Likes: 0
From: Ocean County, NJ
Default LS1 Conversion With Issue of Computer Pulling Timing after Running for a while!

Well we have the full Painless Wiring Harness with Drive By Wire Set-Up, No cats (2) O2 sensors @ bottom of both headers. Computer # 411.

Car runs great but 1st time we had running tuned on Dyno 400HP/385 TQ went out couple days later made couple WOT Passes and drove it home with no issues and parked in garage, cam out next day started car went to go for a ride and it had a bad hesitation which was really the computer pulling 10 degrees of timing with a bit of load on motor.

We Deleted file and reload tune file and went to the track made 12 passes, drove couple days after the track rental, went down to my friends shop to install anti-roll bar and new coil-over set-up, car runs and drives fine under light pedal acceration and after getting there wanted to go to the WAWA and get to pull out and fell on its face with pulling timing under the load again.

There are no codes --- Disconnected battery and computer and reconnected and no change.

Does this sound like its a sensor issue, ground issue, computer issue, or tune issue. Maybe even a parameter in the computer that we are missing to shut off or delete.

Thanks in Advance
Ralph
BoostedLQ9SS/Bu
Reply
Old Dec 14, 2009 | 05:38 PM
  #2  
69LT1Bird's Avatar
11 Second Club
iTrader: (1)
 
Joined: Sep 2007
Posts: 2,310
Likes: 6
From: Lapeer, MI
Default

Post the tune
Reply
Old Dec 14, 2009 | 06:40 PM
  #3  
jimmyblue's Avatar
Moderator
iTrader: (11)
 
Joined: Mar 2002
Posts: 12,604
Likes: 7
From: East Central Florida
Default

If the setup produces a consistent knock retard at any
load-point, you may be driving it into knock learning
(look in the scanner for Knock Learn Factor, 0 is good,
1 is all the way into low octane table). This I think will
not show up as spark retard, only a less than expected
net timing. But it comes from continual knock retard
events, PCM trying to get away from it.

There are half a dozen or so spark retard adders that
you can scan and see who's busy.
Reply
Old Dec 15, 2009 | 12:39 AM
  #4  
BoostedLQ9SS's Avatar
Thread Starter
On The Tree
iTrader: (11)
 
Joined: Nov 2008
Posts: 161
Likes: 0
From: Ocean County, NJ
Default

I am having a friend with HP do a couple datalogs for me so i can see where the issue is being approached.

seems like sharp hit of the gas pedal it shuts it down(bog throttle right down) with it in park but if you gradually bring it up it doesn't seem to do it or very slightly.

Thanks So far for your help.

We will keep an open miind--

Ralph
Reply
Old Dec 15, 2009 | 09:40 AM
  #5  
Steel Chicken's Avatar
TECH Enthusiast
iTrader: (3)
 
Joined: Aug 2005
Posts: 597
Likes: 0
From: Castle Rock, CO
Default

Post logs and tune
Reply




All times are GMT -5. The time now is 10:54 PM.

story-0
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-1
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 | 2026-05-28 11:05:11


VIEW MORE
story-2
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-3
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-4
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-5
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-6
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-7
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-8
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
story-9
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE