Ls harness & computer question

[Tomeal]

I'm getting close to buying a 5.3 engine. Calling local yards to see what they have.

First question:. Can any harness from 99-02 be re-pinned and work with any engine between 99-02? I'm looking at truck engines that are DBC. I'm not going to do DBW.

Second question:. Can a computer from an 02 be programmed to work backwards to an engine as early as 99? One of the computers I can get is the 411 computer from an 02.

Been reading up slot and haven't ran into a solid answer yet. Guess I need to know if I have to stay same year or if there is some flexibility between 99-02.

Thanks in advance.

 

[87National]

I'm getting close to buying a 5.3 engine. Calling local yards to see what they have.

First question:. Can any harness from 99-02 be re-pinned and work with any engine between 99-02? I'm looking at truck engines that are DBC. I'm not going to do DBW.

Second question:. Can a computer from an 02 be programmed to work backwards to an engine as early as 99? One of the computers I can get is the 411 computer from an 02.

Been reading up slot and haven't ran into a solid answer yet. Guess I need to know if I have to stay same year or if there is some flexibility between 99-02.

Thanks in advance.

99-02 are all pretty much the same, although I believe the lq4 Denali and escalade were DBW. O2 sensor wiring may have been slightly different across those years.

Checkout lt1swap.com, he outlines the year-to-year differences.

Can't you just buy a complete pullout so you know everything matches?

 

[Jakefromstatefarm]

99-02 are all pretty much the same, although I believe the lq4 Denali and escalade were DBW. O2 sensor wiring may have been slightly different across those years.

Checkout lt1swap.com, he outlines the year-to-year differences.

Can't you just buy a complete pullout so you know everything matches?

LQ4 is DBW.

I plan to keep the factory harness and computer just in case but I plan to run the Holley terminator.

The DBW harness can be reworked to work with DBC. I think it's 5 wires that have to get moved to different pins in the harness connector at the ECU.

 

[87National]

LQ4 is DBW

As stated....01-02 denali and escalade were DBW. I'm 99% certain 99-02 lq4 powered trucks were DBC. Also, lq4 powered vans were DBC up to around 2006.

 

[Northernregal]

99-03 is the 512k 0411 ECU, it is the gree/red connectors, almost all are drive by cable and few are compatible with DBW, there are a few exceptions but they are rare.

04-07? is the 1024kb ECU, Red/Blue connectors. Most are DBW, some require a separate DBW controller box similar to the earlier DBW in 99-03, and some are stand alone. Later blazer, s10 and express vans had drivers for IAC control and can be used for cable throttle.

You cannot plug a green/red harness into a red/blue ecu, but other than DBW/DBC and IAC you can swap late harness and computer to early motors. There are some emissions stuff that changed, like EGR and air pumps but they can be delete from ECU program.

Now with that said you have to have a compatible tune for the ECU you are using and the IAC/DBW setup for the intake/throttle body but thats pretty easy to figure out.

 

[87National]

99-03 is the 512k 0411 ECU, it is the gree/red connectors, almost all are drive by cable and few are compatible with DBW, there are a few exceptions but they are rare.

04-07? is the 1024kb ECU, Red/Blue connectors. Most are DBW, some require a separate DBW controller box similar to the earlier DBW in 99-03, and some are stand alone. Later blazer, s10 and express vans had drivers for IAC control and can be used for cable throttle.

You cannot plug a green/red harness into a red/blue ecu, but other than DBW/DBC and IAC you can swap late harness and computer to early motors. There are some emissions stuff that changed, like EGR and air pumps but they can be delete from ECU program.

Now with that said you have to have a compatible tune for the ECU you are using and the IAC/DBW setup for the intake/throttle body but thats pretty easy to figure out.

Red/blue is 99-02. Green/blue is 03+

 

[Northernregal]

Red/blue is 99-02. Green/blue is 03+

I could be wrong on color, it has been a long time since I looked at stock ECU. Thank you!

 

[81cutlass]

01-02 lq9 and traction control 5.3's were DBW. I have a DBW harness in my 2+2. It does make cruise control really easy.

The DBW can be downgraded to DBC by repinning but it is quite a few wires. The bundle of wires going to the TAC module that controls the DBW TB is THICK. Unless you find the rare 5.3 or lq9 it's unlikely you will run into one. DBW isn't a problem. It takes a tiny amount of tuning to get past some safeties but it's workable.

The later 01/02 PCM's are a bit better as far as capability than the 99-00 style. The 02 tahoe flex PCM is kinda the one to get because it can do flex fuel E85 which is awesome for boost.

99-00 had one style of 02 sensor and 01-02 used a different one. Heated or grounded different or something.

But yeah 99-02 is pretty flexible backwards and forward compatible.

 

[Tomeal]

Thanks guys. All the info I was reading pointed in that direction. Just none flat out said it.

Can't you just buy a complete pullout so you know everything matches?

All the yards separate everything to get you to pay more. And that age range of engines don't seem to flooding into the yards anymore.

 

[87National]

Thanks guys. All the info I was reading pointed in that direction. Just none flat out said it.


All the yards separate everything to get you to pay more. And that age range of engines don't seem to flooding into the yards anymore.

Was thinking more CL or FB.....in my area there are at least 10 complete 5.3l pullouts within a 100 mile radius for $5-700.