PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Help Disabling Flex Fuel with EFI

Thread Tools
 
Search this Thread
 
Old Apr 16, 2018 | 03:53 PM
  #1  
timmay208's Avatar
Thread Starter
TECH Resident
iTrader: (2)
 
Joined: Oct 2013
Posts: 829
Likes: 0
From: CDA, ID
Default Help Disabling Flex Fuel with EFI

Ok have a 2002 5.3 Flex fuel PCM/Engine in my 87 Silverado. I keep getting P0178 Codes even though i have it set not to report DTC and have it set to no MIL. Also get code P1638 which also is set not to report and no MIL.

Calibration 12216121 and OS 12216125

No other codes everything seems to run fine, but almost every time i start the truck not long after the CEL comes on with those 2 codes. Am i missing something here or what cause ive disabled everything i can find related to emissions and Flex fuel

Also have gotten a P0507 High Idle code randomly, mostly happens when truck is cold and you start it will rev up to 1600-1800 then go back to normal. Everything i can read leads to a vac leak but cannot fine one and other than that it idles just fine not jumpy or anything and doesnt idle high after the initial start

any insight would be greatly appreciated
Reply
Old Apr 19, 2018 | 08:33 AM
  #2  
PeteS160's Avatar
TECH Enthusiast
5 Year Member
 
Joined: Oct 2017
Posts: 567
Likes: 159
Default

Post your file and I'm sure someone can take a look at it for you.
Reply




All times are GMT -5. The time now is 02:11 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