Engine Swap - Engine won't crank w/ key but does when hot wired
#1
TECH Resident
Thread Starter
iTrader: (5)
Join Date: Nov 2006
Location: Houston
Posts: 780
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
Swapped in a 2005 6.0L harness/pcm in a 2005 silverado that originally had a 4.3L.
I used the 6.0L PCM and tuned out VATS.
Got the engine in and went to turn the key, but the engine will not crank. The vehicle shuts the headlights off, etc. as if it is sending power to the starter, but it is not.
I pulled the fuse box and using a wire I connected power straight to the starter, bypassing the need for a key. w/ the key in the 'on' position, The engine cranked and fired right up and ran when 'hot wiring' it.
So, VATS is tuned out. It is getting fuel and spark, something is just preventing the key from sending the signal to power the starter --- is there anything else I need to do to allow this thing to crank using the key???
I used the 6.0L PCM and tuned out VATS.
Got the engine in and went to turn the key, but the engine will not crank. The vehicle shuts the headlights off, etc. as if it is sending power to the starter, but it is not.
I pulled the fuse box and using a wire I connected power straight to the starter, bypassing the need for a key. w/ the key in the 'on' position, The engine cranked and fired right up and ran when 'hot wiring' it.
So, VATS is tuned out. It is getting fuel and spark, something is just preventing the key from sending the signal to power the starter --- is there anything else I need to do to allow this thing to crank using the key???
#3
Custm2500's Rude Friend
iTrader: (17)
![Default](https://www.performancetrucks.net/forums/images/icons/icon1.gif)
Ground on the rear pass side of block for me. Just went through this.
As mentioned, check all the grounds just to be sure.
Make sure you also have a ground strap to Firewall and a ground to frame since this was an engine swap.
The main battery Negative cable will have a ground directly to block with a smaller wire going under the core support to the frame mount. The main Ground will also have control module on it which must be attached or the engine will not run. I Had a tow truck driver cut the small wire and it would crank but not start.
As mentioned, check all the grounds just to be sure.
Make sure you also have a ground strap to Firewall and a ground to frame since this was an engine swap.
The main battery Negative cable will have a ground directly to block with a smaller wire going under the core support to the frame mount. The main Ground will also have control module on it which must be attached or the engine will not run. I Had a tow truck driver cut the small wire and it would crank but not start.
Last edited by 1FastBrick; 10-30-2015 at 08:21 PM. Reason: mo details...
Thread
Thread Starter
Forum
Replies
Last Post
Velocity1
GMT 800 & Older GM General Discussion
1
10-06-2015 02:42 AM
Wrecker 426
Tuning, Diagnostics, Electronics, and Wiring
1
09-30-2015 09:39 PM