Good stuff. I’m getting ready to do a test start on my LS also. I am trying to find out the type of cam I have in it. The engine shop I bought it from said it had a BTR cam installed as they we’re going to use the engine for a drag car, but decided to go with a big block instead. I’m waiting on a response from the shop.
Yeah either specs from the shop or pull the rear cover and get the part number off the back of the cam. BTR has TONS of cams so it could be anything. Good luck!!
Hey man this video is exactly what I needed for my build! Just one question. In your video, when you’ve consolidated all of the wires into 3 basic cables, I see a computer on the table in the background. Will that computer hinder a start up if I don’t have it? Thanks for the help and the awesome video!
I used the computer to remove de-activate VATS in the PCM. These engines won't run by themselves out of the vehicle unless the VATS programming in the pcm is turned off.
Just finish building a lq4, I'm trying to do the same thing with a ebay stand alone, but fuel pump isn't kicking on. Hopefully I can get it to work today.
I have a similar engine ls3, I did the electrics as you have in the video. We programmed the computer and turned off the "vats system". Unfortunately, the engine did not start. High voltage comes to the spark plugs, but no impulse comes to the injectors. Maybe you can advise me what could be the reason. Diagnostics shows me the error P0315. The sensor is working. Thank you very much in advance
If it has spark but the injectors aren't pulsing, first I would make sure they have a good 12V+ supply, then I would triple check that all the grounds in the harness are connected to the engine block on a good clean surface. If all that checks out and you still don't have injector pulse I would log the pcm inputs and make sure it has good cam and crank position signals. Double check also that when you removed VATS you did a WRITE ENTIRE because it won't actually remove vats any other way.
@@MohawkMotors Many thanks for the feedback and comments. I live in another country "Asia in Georgia". Watts was deleted in America and I don't know exactly how they did it. I will write a letter and see what they say.
@@MohawkMotors Hello, I saw your message late. I started the engine. I checked everything before and everything was fine. The only reason why it did not work was the starter relay, it did not turn on and the computer perceived it as an error, it did not allow the engine to start.
Hello. If you can draw me a diagram of how the starter relay turns on. One wire comes out of the computer "starting charging system". Thank you very much in advance
The starter relay is very simple. The control side and load side are fed battery 12V +. The other terminal of the control side is run to the pcm, when you turn the key to the start position, the pcm grounds the control side and completes the circuit, which closes the load side of the relay. The other terminal of the load side of the relay is connected to the exciter post on the starter. SO, when you turn the key to the start position, the pcm provides ground to the control side of the starter relay, that activates the relay and closes the load side of the relay, which allows battery 12V+ to flow to the exciter post on the starter, which activates the starter and cranks the engine.
@@MohawkMotors Hello. thank you for advice. I want to tell you that I do not have a key block, nor a comfort block. I only have the engine and gearbox wiring. The starter wire comes out of the computer, but no action can come out of it, because the comfort unit and key are not connected. I am forced to put one relay in this circuit to false and put another second relay with a simple connection, which will work the starter.
I made a portable fuel sending unit, it's a 5 gallon bucket with a fuel sending unit out of a truck I parted out, just connect the feed to the feed and return back to the bucked and give the pump 12V and a ground.
@@MohawkMotors thank you i had someone do n ls swap for me cut up all my wiring so now im thinking this is the way to go thank you got a new subscriber
My harness never came with a fuse block it came just as yours is with the black block only. Could i do what youve done here but have the power circuit manually turned on and off with a switch (as the fuel pump will be) and run this as a long term in the car solution?
Yes, you could do it that way. I would highly recommend a fuse of some kind in the system as a safety but you could absolutely control it with a simple on off switch. (A relay would be a good idea, too much amperage going through the circuit for a switch to last very long)
@@MohawkMotors okay thank you very much! I don't know anything really about electrical stuff but I'm learning. Was tempted to buy a cheap standalone Amazon harness but I have the original one so might as well use jtn
Just ls swapped my 03 Chevy Silverado it was a v6 it runs and drives but wont shut off when i turn the key off and wont charge what do u think it could be
If you're using and 04 harness and computer in an 03 truck, it should work. If you didn't modify the harness in any way then you may just have a bad connection somewhere. Also did you convert the 01 motor to drive by wire to work with the 04 harness and computer or are you using a van harness and computer to run the 01 engine as drive by cable?
@@MohawkMotors yes I changed it to drive by wire my harness was cut in half when I got it and I got it wired to what I thought was right and it runs but doesn't shut off at the key u shut the lights off after the key is on truck still run shut the lights off and the truck shuts off I didn't know if u would have like any idea on the wire color or a video something I could look at to correct what I did wrong
did u have a pedal hooked up when running it? i have vats turned off on my pcm, i didnt select write entire when i did it though. but it will fire and run for half a second then shut off
I wanted this video to be for demonstration of how to run an engine out of a vehicle for people. A lot of times someone buys an engine and it doesn't come with the fuse block, or even the fuse block connector, just a chopped off harness, I was hoping for this to help by not relying on those being there.
Do you have hp tuners or a scan tool that will allow you to live view the pcm inputs? No injector pulse and no spark when you have goo power and ground supplied would make me think you aren't getting crank position signal to the pcm, it's the only other ingredient the pcm needs to fire the injectors and trigger spark.