Which Engine Harness Do You Use?
Thread Starter
Staging Lane
Joined: Oct 2007
Posts: 58
Likes: 0
From: Mill Creek/Lynnwood, WA
Which Engine Harness Do You Use? I have decided that I am going to go ahead and purchase a standalone wiring harness for my 5.3 flex-fuel engine from an 04 Tahoe. Which engine harnesses are some of you using or recommending? It is a flex-fuel engine and I know there are some of the companies that are not offering the harnesses for the flex-fuel injectors. I am also running dual electric fans instead of the mechanical fan that came with the motor. Fuel pump is an in-tank pump from a 2000 transam.
Any input is appreciated.
Any input is appreciated.
Unless you got the fuel composition sensor AND are planning an E85 compatible fuel system (plastic tank, all plastic or stainless line and fittings), dont worry about the E85.
The truck ecu has an electric fan provision. You can also use the another output (AC recirc, I think) for a second fan.
Fuel pump is the same regardless. Oh yeah, is it DBW?
The truck ecu has an electric fan provision. You can also use the another output (AC recirc, I think) for a second fan.
Fuel pump is the same regardless. Oh yeah, is it DBW?
Last edited by garys 68; Nov 16, 2012 at 07:00 PM.
Teching In
Joined: Nov 2012
Posts: 24
Likes: 0
From: Jackson, TN
The only difference that I know between flex fuel and nonflex fuel engines are the injectors. If you dont plan on using the E85 you can swap over to nonflex fuel injectors and just use a regular 5.3 harness and pcm. At least thats what I would do...
Staging Lane
Joined: Jan 2009
Posts: 66
Likes: 0
From: Weeki Wachee,Florida
Trending Topics
Flex fuel injectors use the same connector as newer LSx engines, so thats a non-issue. You dont have to keep the E85 option when converting, can just as easily tune it for the slightly larger flex injectors and call it a day
Use whatever harness you have available for a DIY install or tell the mfr what you're building
Ive used every sort of harness out there for conversions, trucks of all flavors, Fbodys 98 and the 99+. My last harness was a super budget build from half a late 90's S10 harness and half a late 90's 3.8L FWD harness. Cost me $20 in the end
Use whatever harness you have available for a DIY install or tell the mfr what you're building
Ive used every sort of harness out there for conversions, trucks of all flavors, Fbodys 98 and the 99+. My last harness was a super budget build from half a late 90's S10 harness and half a late 90's 3.8L FWD harness. Cost me $20 in the end
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Thread Starter
Staging Lane
Joined: Oct 2007
Posts: 58
Likes: 0
From: Mill Creek/Lynnwood, WA
Thanks for all the input. I have the original harness from the engine including the drive by wire gas pedal as well as the fuse panels (I think). Looking at a pin out chart and wiring diagrams right now. May try and modify this thing myself.........
I will keep the flex fuel injectors, but have it programmed out.
If I want to extend the wires so that the PCM can be located under the seat, is it OK to cut the wires and splice new wire in between the sensor and PCM connection?
I will keep the flex fuel injectors, but have it programmed out.
If I want to extend the wires so that the PCM can be located under the seat, is it OK to cut the wires and splice new wire in between the sensor and PCM connection?
Use this for pinouts.
https://spreadsheets.google.com/spre...KSkg2Z3c&hl=en
Anything that says NOT can be removed.
Yes, you can extend the wires but it takes a lot of wire and added work.
https://spreadsheets.google.com/spre...KSkg2Z3c&hl=en
Anything that says NOT can be removed.
Yes, you can extend the wires but it takes a lot of wire and added work.
Registered User
Joined: Aug 2023
Posts: 1
Likes: 0
5.3 flex engine wiring harness I have a 2007 Surburban LT flex with an engine wiring harness shortage.
VIN# 3GNFK16397G144994
looking for a replacement over a year now. can someone please advice me on this issue? the shortage in volts is coming form and upper oxgen sensor and my truck has completely shut off several times... please advice and thank you in advamce
VIN# 3GNFK16397G144994
looking for a replacement over a year now. can someone please advice me on this issue? the shortage in volts is coming form and upper oxgen sensor and my truck has completely shut off several times... please advice and thank you in advamce
