[LS Swap] Didn't Start :(

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Oct 29, 2012 | 08:10 PM

#41

wcsinx

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Quote:

Originally Posted by PUNISHER VETTE

I stole power for a few things from the BAT terminal in the fuse box. It's constant 12v off as well as run/crank. Which makes it weird that when the brakes are pressed it causes some sort of surge or break for that split second to cause the relay to come on... I guess to make things easy I'll just find another constant power source...

interesting ... that should theoretically be fine

I wonder if it's finding a ground through the brake light wiring somewhere?

Oct 29, 2012 | 08:52 PM

#42

Neptune75

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From: Clio Mi

Congrats.... nice to see you have the LS started

Oct 30, 2012 | 02:16 PM

#43

PUNISHER VETTE

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From: Fisher, IL

Well I don't understand this thing but I'll keep trying.

Gave the fuel pump it's own power source(tapped into the two fan power lines coming off the alternator)

Anyway, hit the brake pedal and the pump still comes on...

I guess I gave the TCC/brake signal power from the same source.

This is the only constant in the two setups so it has to be the wire linking the fuel pump to the brakes somehow.

Also...took the mufflers out of my sidepipes... it's going to sound nice!

Oct 30, 2012 | 03:31 PM

#44

PUNISHER VETTE

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From: Fisher, IL

Muffler inserts out, hard to tell but nicer sounding.
Except with them out I threw a Bank 1 O2 sensor warning light. P0134
http://s41.photobucket.com/albums/e2...t=MVI_0513.mp4

Also. Black watery liquid leaking out of the pipes. Just bad stuff getting cleaned out?

I'll keep chipping away at the issues

trying to get the clutch to work right. so far even when bleed it's not disengaging completely so I can't get into gear or out of gear smoothly. and when in gear and the clutch pushed in it's not stopping the shaft like it should.

the brake/fuel pump issue.

fans never turned on even though i let the car warm up to 188degrees.

Need a proper air intake with filter.

Oct 30, 2012 | 04:23 PM

#45

riggs 74

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From: springfield ohio

Didn't your reworked harness come with a fuse relay setup for the fuel pump along with other much needed fusing for the LS motor? If so it should have its own fuse and relay built in for the fuel pump. Your fuel pump wiring should have nothing to do with the Brake light circuit unless you had ran the fuel pump lead to the brake circuit, take some time and trace that out. If you don't have a fuse or relay for the fuel pump, you should install one.
Your wiring altogether seams much different than mine.

Riggs

Oct 30, 2012 | 05:24 PM

#46

PUNISHER VETTE

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From: Fisher, IL

Quote:

Originally Posted by riggs 74

Just did a google search and found a guy who seemed to have the same issues I am having. Looks like maybe not enough grounding causing some of the frame to become a 12v source that the pump is using to prime?

after reading his post I also noticed my pump primes not only with the brakes but with the hazzard lights and regular lights, and blinkers

either that or I must have a short somewhere causing issues?

Quote:

So I ended up figuring out why the lights/brakes were priming the fuel pump.

Note: NEVER put any engine grounds on an aluminum intake. Found out aluminum was not a good enough ground for my rear ECM grounds that were supposed to be originally at the back of the cylinder head.

So I went ahead and moved the ECM grounds to the back of the cylinder head where they were originally before I had swapped my engine.

Last edited by PUNISHER VETTE; Oct 30, 2012 at 06:00 PM.

Oct 30, 2012 | 06:01 PM

#47

riggs 74

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From: springfield ohio

If you haven't taken care of all the main grounds yet, I would start there, the grounds cause so much trouble in the electrical system.

Riggs

Oct 30, 2012 | 06:31 PM

#48

PUNISHER VETTE

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From: Fisher, IL

Quote:

Originally Posted by riggs 74

If you haven't taken care of all the main grounds yet, I would start there, the grounds cause so much trouble in the electrical system.

Riggs

I took my grounds off today and sanded them all and sanded the frame to bare metal thinking my powder coating was causing issues and that didn't fix anything.

It's taking me forever to read the guys two threads he had on two different forums but it's good info....although a slightly different engine/car.

I'm back to thinking it's an ECM issue telling the pump to prime for some reason with the light circuit. But the two aren't connected anywhere unless there's a short...