Code P0343 - LS3 conversions opinions please
Thread Starter
Racer
Joined: Aug 2003
Posts: 348
Likes: 1
From: Sacramento CA
Code P0343 - LS3 conversions opinions please
I started my newly installed LS3 for the first time today, and I immediately got DTC P0343 - Camshaft position sensor high input. I've read some threads that say this DTC is usually caused by loose cam bolts. I had a shop assemble the bottom end, cam, timing chain (In-Motion, LS2/LS3 double roller), front & rear cover, and valley cover. I installed the motor, heads, and everything else myself.
What are the chances the shop didn't tighten/install the camshaft bolts? Is it worth tearing the front of the motor back down? Is there anything else I can do before I consider taking the motor apart? Is it possible since the cam sensor has been moved to the front cover that this is just a simple tuning issue?
What are the chances the shop didn't tighten/install the camshaft bolts? Is it worth tearing the front of the motor back down? Is there anything else I can do before I consider taking the motor apart? Is it possible since the cam sensor has been moved to the front cover that this is just a simple tuning issue?
Tech Contributor
Joined: Jan 2007
Posts: 19,388
Likes: 1,134
From: Dyer, IN
I started my newly installed LS3 for the first time today, and I immediately got DTC P0343 - Camshaft position sensor high input. I've read some threads that say this DTC is usually caused by loose cam bolts. I had a shop assemble the bottom end, cam, timing chain (In-Motion, LS2/LS3 double roller), front & rear cover, and valley cover. I installed the motor, heads, and everything else myself.
What are the chances the shop didn't tighten/install the camshaft bolts? Is it worth tearing the front of the motor back down? Is there anything else I can do before I consider taking the motor apart? Is it possible since the cam sensor has been moved to the front cover that this is just a simple tuning issue?
What are the chances the shop didn't tighten/install the camshaft bolts? Is it worth tearing the front of the motor back down? Is there anything else I can do before I consider taking the motor apart? Is it possible since the cam sensor has been moved to the front cover that this is just a simple tuning issue?
Le Mans Master
Joined: Jan 2009
Posts: 6,226
Likes: 33
From: Morton illinois
St. Jude Donor '14-'15
i got this as well, along with my bud who did a LS7. if your cam sensor is from Katech, i believe some of them were rewired backwards. Get ahold of Katech and see what they say. The part that plugged into the front cover had to have one of the wires switched.
When you go to start it, is it just winding up but not firing, then you try again and it starts?
is it the one that ties in the MAP sensor and knock sensors?
When you go to start it, is it just winding up but not firing, then you try again and it starts?
is it the one that ties in the MAP sensor and knock sensors?
Thread Starter
Racer
Joined: Aug 2003
Posts: 348
Likes: 1
From: Sacramento CA
yes, about half the time the car start right up. The other half I have to crank 5-10 seconds, or try a second time.
I bought the front cover from hinson or texasspeed, I can't remember which. Anyway, the cover already had the sensor installed.
And yes, the cam sensor extender was on the same harness as the knock sensors.
thanks for that info, I would have never thought of that. I did notice 1 or 2 of the cam sensor extension wires didn't match the originals. when i get home I'm going to check the harnesses again and see if anything is crossed.
I bought the front cover from hinson or texasspeed, I can't remember which. Anyway, the cover already had the sensor installed.
And yes, the cam sensor extender was on the same harness as the knock sensors.
thanks for that info, I would have never thought of that. I did notice 1 or 2 of the cam sensor extension wires didn't match the originals. when i get home I'm going to check the harnesses again and see if anything is crossed.
Thread Starter
Racer
Joined: Aug 2003
Posts: 348
Likes: 1
From: Sacramento CA
i got this as well, along with my bud who did a LS7. if your cam sensor is from Katech, i believe some of them were rewired backwards. Get ahold of Katech and see what they say. The part that plugged into the front cover had to have one of the wires switched.
When you go to start it, is it just winding up but not firing, then you try again and it starts?
is it the one that ties in the MAP sensor and knock sensors?
When you go to start it, is it just winding up but not firing, then you try again and it starts?
is it the one that ties in the MAP sensor and knock sensors?
Tech Contributor
Joined: Jan 2007
Posts: 19,388
Likes: 1,134
From: Dyer, IN
Thank you VGLNTE1! Sure enough, the wires on the cam sensor harness extension were reversed. The three wires for the cam sensor consist of a red one, a pink one in the center, and a black (with white stripe) one. The red and black were reversed. Car starts up quick just like it should, no MIL either.
