Changing timing.....
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1st Gear
Joined: Aug 2019
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Changing timing.....
I have a 2000 c5 that has been ls6 swaped and one day it started running rough. At first I thought it was a dead cylinder but it turns out it is the car adjusting timing. It will run great then all of the sudden run poorly and a few minutes later it will run great again and it does that back and forth.I am not sure why it is doing that. I have checked for vaccum leaks and i have replaced the front two O2 sensors. I am not sure where else to check and looking for some advice. I am afraid the PCM is going bad. Also, my big issue is, it is not throwing any codes......
Last edited by Michael D. Brown; Aug 17, 2019 at 06:33 PM.
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these cars adjust timing constantly due to varying conditions so that is normal, is the cel on?... you need to pull and check the codes to point you in the right direction and hook it up to a scanner or datalogger to see what's going on
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Melting Slicks
Joined: Feb 2001
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If you put a LS6 engine in the car there are numerous changes in the PCM that would needed to be made to make the car run smoothly, a scan log and dtc codes will help with the solution. If their is no disruption in the air intake, the timing.VE,Torque curve, etc of the LS6 vary greatly from the 2000. You might check with Dynamic Corvettes in Saginaw if they still do tuning on the C5
Racer
Joined: Oct 2003
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From: Venice, Florida
How did you come to the conclusion that it's pulling timing? Also, If say you happen to have gotten some bad gas it could be switching back and forth between the high and low spark tables if it's getting any knock. I'm thinking it's something other than the timing unless you can give good validation that it is. We need more info.
