Ls swap problems
Thread Starter
Teching In
Joined: Apr 2014
Posts: 1
Likes: 0
From: ROYSTON, GEORGIA
Ls swap problems I swapped a 07 truck 5.3 into my 69 Camaro with a turbo. I have a new harness from GM Performance with a new E67 computer, the computer has been tuned for my setup. The car will try and run but goes dead after a couple of seconds, sometimes it will crank and run for about 10 seconds and then just shut off, kinda like it's in a limp mode. Fuel pressure is good and all harnesses are new. It has new coils, plugs, and wires. It's giving me a po355 code, I have swapped coils and checked all connections the grounds seem to be good also. Asking for help please....
On The Tree
Joined: Nov 2014
Posts: 102
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From: NW Florida
Try unplugging the MAF as well if you have that installed. Mine wouldn't run right with the MAF plugged in, like yours it ran for a few seconds and died, but it ran fine if I unplugged it. Once I got the intake tubes installed and plugged the MAF back in it ran like a champ. Cheap/easy possibility and worth a try.
Rock
Rock
Last edited by rockusaf; May 2, 2017 at 08:12 PM. Reason: clarification
What type of MAF are you using? Is it the truck MAF that came with the engine or a card style MAF?
On mine, I had to switch the pink and black wires on the MAF connector due to changing from the LY6 screen style MAF to an LS7 card style MAF. I had a similar issue where might it would sometimes fire for a second or two, then die.
On mine, I had to switch the pink and black wires on the MAF connector due to changing from the LY6 screen style MAF to an LS7 card style MAF. I had a similar issue where might it would sometimes fire for a second or two, then die.
Launching!
Joined: Feb 2015
Posts: 245
Likes: 21
What type of MAF are you using? Is it the truck MAF that came with the engine or a card style MAF?
On mine, I had to switch the pink and black wires on the MAF connector due to changing from the LY6 screen style MAF to an LS7 card style MAF. I had a similar issue where might it would sometimes fire for a second or two, then die.
On mine, I had to switch the pink and black wires on the MAF connector due to changing from the LY6 screen style MAF to an LS7 card style MAF. I had a similar issue where might it would sometimes fire for a second or two, then die.
Unplugging the MAF sensor will put the ECM in default mode (speed density) and it should run. It may take a few attempts to get it to catch.
Joined: Mar 2007
Posts: 1,145
Likes: 51
From: Saskatchewan, Canada - where arguing "DA" is for the slow and weak...
$5 says he is using a custom OS with the turbo and the MAF is absent, however the MAF was not failed properly (ie not reporting the code) allowing the ECM to go into SD.
