LS3 swap, keeps going in low power mode
Thread Starter
Instructor
Joined: Aug 2022
Posts: 145
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LS3 swap, keeps going in low power mode
I got a "new" C5 Z06 that had a GM LS3 crate motor already installed in it. Well it keeps throwing 3 trouble codes at the same time and then going into low power mode after a bunch of warning messages pop up on the dash. Its throwing:
P0332 - knock sensor 2
P0327 - Knock sensor 1
P1515 - electronic throttle system
It throws them as soon as I do a hard acceleration and hit in the 5k rpm ballpark. After going through the 100's of receipts that came with the car I noticed it was in the shop multiple times getting the knock sensors checked out and always came back "fine". I am wondering if there may be some type of issue with the the engine swap or the tuning that went with it, but have no clue where to begin to find the issue. My ideas if all the hardware is intact and wiring are intact like I expect:
PCM issue?
Tuning Issue?
Possible the wrong parts were installed during the engine swap, but I dont know what the right parts should be?
ANy help would be appreciated
P0332 - knock sensor 2
P0327 - Knock sensor 1
P1515 - electronic throttle system
It throws them as soon as I do a hard acceleration and hit in the 5k rpm ballpark. After going through the 100's of receipts that came with the car I noticed it was in the shop multiple times getting the knock sensors checked out and always came back "fine". I am wondering if there may be some type of issue with the the engine swap or the tuning that went with it, but have no clue where to begin to find the issue. My ideas if all the hardware is intact and wiring are intact like I expect:
PCM issue?
Tuning Issue?
Possible the wrong parts were installed during the engine swap, but I dont know what the right parts should be?
ANy help would be appreciated
Thread Starter
Instructor
Joined: Aug 2022
Posts: 145
Likes: 10
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Thread Starter
Instructor
Joined: Aug 2022
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Safety Car
Joined: Aug 2011
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From: Portland OR
Stock C5 runs the LS2 TB just fine. One tune change to do that.
P1515 could be a gas pedal issue, TAC module issue or a TB issue.
So your hard acceleration is foot to the floor? Does it do it when you are accelerating hard but not foot to the floor?
Could be a tune issue if it repeats this every time.
If it’s just the accel causing it, could be a bad connection.
At the very least I’d find and clean every connector in the TPS system.
CRC electronics cleaner works well. Inspect the pins as well.
To check the tune would require someone with HP Tuners to read the file. Then it could be posted here.
Those knock sensor codes should be turned off in the tune. LS3 knock sensors don’t work with the C5 ECU.
And one last thing. Does the car have a crank trigger converter box?
Ron
P1515 could be a gas pedal issue, TAC module issue or a TB issue.
So your hard acceleration is foot to the floor? Does it do it when you are accelerating hard but not foot to the floor?
Could be a tune issue if it repeats this every time.
If it’s just the accel causing it, could be a bad connection.
At the very least I’d find and clean every connector in the TPS system.
CRC electronics cleaner works well. Inspect the pins as well.
To check the tune would require someone with HP Tuners to read the file. Then it could be posted here.
Those knock sensor codes should be turned off in the tune. LS3 knock sensors don’t work with the C5 ECU.
And one last thing. Does the car have a crank trigger converter box?
Ron
Thread Starter
Instructor
Joined: Aug 2022
Posts: 145
Likes: 10
Stock C5 runs the LS2 TB just fine. One tune change to do that.
P1515 could be a gas pedal issue, TAC module issue or a TB issue.
So your hard acceleration is foot to the floor? Does it do it when you are accelerating hard but not foot to the floor?
Could be a tune issue if it repeats this every time.
If it’s just the accel causing it, could be a bad connection.
At the very least I’d find and clean every connector in the TPS system.
CRC electronics cleaner works well. Inspect the pins as well.
To check the tune would require someone with HP Tuners to read the file. Then it could be posted here.
Those knock sensor codes should be turned off in the tune. LS3 knock sensors don’t work with the C5 ECU.
And one last thing. Does the car have a crank trigger converter box?
Ron
P1515 could be a gas pedal issue, TAC module issue or a TB issue.
So your hard acceleration is foot to the floor? Does it do it when you are accelerating hard but not foot to the floor?
Could be a tune issue if it repeats this every time.
If it’s just the accel causing it, could be a bad connection.
At the very least I’d find and clean every connector in the TPS system.
CRC electronics cleaner works well. Inspect the pins as well.
To check the tune would require someone with HP Tuners to read the file. Then it could be posted here.
Those knock sensor codes should be turned off in the tune. LS3 knock sensors don’t work with the C5 ECU.
And one last thing. Does the car have a crank trigger converter box?
Ron