PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Very weird problem, PO507

Thread Tools
 
Search this Thread
 
Old Jan 3, 2007 | 04:24 PM
  #1  
TroubledWine3's Avatar
Thread Starter
TECH Resident
iTrader: (3)
 
Joined: Nov 2004
Posts: 795
Likes: 0
From: North Carolina
Default Very weird problem, PO507

My buddy has a 99 Trans Am. Patriot Stage 2 LS6 heads w/ bigger valves, G5X2 cam, LS6 intake, stock TB and MAF, stock pulley, dual electric cutouts. 6 spd. car.

It just started this **** the other day after we took it down the road and got on it a little bit.

With the cutouts CLOSED, it idles fine. With the cutouts OPEN, the idle consistently keeps climbing past 3 grand. But as soon as you close them, the idle drops right back down to 850-900 like it should be.

Scanned it with some bullshit OBD2 scan tool and it threw a PO507 code, which is "Idle control system RPM high". Also, every now and then(not all the time), the SES light flashes about 5-6 times and goes off.

Any ideas?
Reply
Old Jan 3, 2007 | 04:32 PM
  #2  
pdanrichey's Avatar
TECH Resident
iTrader: (4)
 
Joined: Nov 2004
Posts: 768
Likes: 1
From: Keller, TX
Default

flashing SES usually means a random misfire detected. Where did he install the cutouts in the exhaust system? Too close to the front O2s could definetely jack something up. The front O2 on the passenger side is much further back in the piping compared to the driver's side.
Reply
Old Jan 3, 2007 | 04:36 PM
  #3  
TroubledWine3's Avatar
Thread Starter
TECH Resident
iTrader: (3)
 
Joined: Nov 2004
Posts: 795
Likes: 0
From: North Carolina
Default

Yeah they are pretty close to the headers on the ORY. And if he's driving the car, 99.9% of the time, the cutouts are open. My first thought was an o2 but it didn't throw an o2 code.
Reply
Old Jan 3, 2007 | 10:41 PM
  #4  
pdanrichey's Avatar
TECH Resident
iTrader: (4)
 
Joined: Nov 2004
Posts: 768
Likes: 1
From: Keller, TX
Default

It may not throw an O2 code if it's constant...the O2 will just report what it's getting. If it's sensing a lot of oxygen in the pipes, it's going to want to dump fuel into the engine...thus the idle rises. I am by no means and expert, but if it only happens when they're open...that could be your problem.
There are some other things to check though...a couple of searches can point you in the right direction about high idles.
Reply




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

story-0
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-1
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-2
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-3
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-4
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-5
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
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE