• Notice for iPhone users: DO NOT use the image size reduction option when uploading photos to the forum. This causes portrait images to post as landscape. We have added a warning to the image insert pop-up as well.

ECU Mounting Location & Wiring Harness

93_Fummins

CJ-8 Member
City
Edmond
State
OK
I'm about to begin diving into a pullout LS engine harness and attempting a DIY standalone. Where are some of you guys mounting your ECU and how are you running your harness?

Also, what are some good standalone harnesses should one abandon the DIY route?

Any input is greatly appreciated by myself and anyone else in the same position.
 

sdsupilot

CJ-8 Member
Member
City
OKC
State
OK
Went the DIY route with the factory 89 s10 harness. Not many in cabin choices for computer mounting. I removed the glove box and the computer sits on the heater box and bottom lip of the dash.

C4306B55-3F93-4FC9-BDC4-249994A8C77D.jpeg

This is where I drilled the hole for the harness to run. Right beside this vent tube. The harness then comes in over the heater box.
E10F0399-728E-4429-91D7-415E3D8A3336.jpeg
 

Randyzzz

Blown Budget
BENEFACTOR
Gold Member
Lifetime Member
SOA Member
City
Redmond
State
OR
On Copper, I mounted the ECU under the dash to the left of the column. It sounded like a good idea at first but it ended up being a lot of wires in a very cramped space, and it would have been a major pain if I had ever had to remove it for service. On Red I'm planning on mounting it to the firewall under the hood, right below the bulkhead connector with the wire connector pointing down. TAC module nearby. I figure they were designed to withstand engine compartment heat so why not.

Also on Copper I had integrated the LS wiring and fuses into the main harness that I had built. 1 fuse panel for everything. On Red the LS will have its own fuse panel under the hood, and the body harness will have its fuse panel in the stock location. I'm using another MNStar police car panel under the hood so there will be plenty of fuses and relays for everything.

1633541696187.jpeg
 
Last edited:

Spieg

Scrambler Junkie
Lifetime Member
City
Aurora
State
CO
Not a chevy, but my ford ECU sits on top of the heater box just like the AMC ECU did.
 

JPCRZY

Legacy Registered User
City
Lakewood
State
Co
On my 304 with Howell it is mounted on top of the heater box using the strong plastic “Velcro”. On my LS I plan to do the same. Both harnesses go through the factory computer harness location using the factory grommet that I split to fit around the harness.
 
Top