Drivability Issue
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Joined: Oct 2022
Posts: 74
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From: Las Vegas NV
Drivability Issue
2008 LS3 Automatic.
Bone stock.
Been experiencing an issue that I don't even know where to begin.
At steady state cruising - highway speeds; I start getting a periodic (for lack of a better term) misfire.
It honestly "feels" like the car does when the stability nannies kick in - like either fuel or spark is cut off for a split second.
Or if it was an older car; I would say the timing was off.
So it's just drive along fine and then the engine "bogs" then right back to running - the stutter is extremely short duration.
After it starts behaving this way - then it continues to stumble just slightly until I am finished driving - sometimes feeling like its about to stall when taking off from a stop.
I have changed plugs and wires - car normally idles fine.
Car has plenty of power (other than the stumble) - no CEL or codes.
I have had it throw a "Service Traction Control" on the DIC - but only momentarily and only when coming downhill on a reasonably steep mountain road.
I don't know if its fuel - spark - nannies or where to even start.
Bone stock.
Been experiencing an issue that I don't even know where to begin.
At steady state cruising - highway speeds; I start getting a periodic (for lack of a better term) misfire.
It honestly "feels" like the car does when the stability nannies kick in - like either fuel or spark is cut off for a split second.
Or if it was an older car; I would say the timing was off.
So it's just drive along fine and then the engine "bogs" then right back to running - the stutter is extremely short duration.
After it starts behaving this way - then it continues to stumble just slightly until I am finished driving - sometimes feeling like its about to stall when taking off from a stop.
I have changed plugs and wires - car normally idles fine.
Car has plenty of power (other than the stumble) - no CEL or codes.
I have had it throw a "Service Traction Control" on the DIC - but only momentarily and only when coming downhill on a reasonably steep mountain road.
I don't know if its fuel - spark - nannies or where to even start.
Melting Slicks
Joined: Dec 2003
Posts: 2,339
Likes: 722
From: Chicago N/W Suburbs
Disconnect the wire harness at each injector and intermediate connector on that harness. Work your way down to the ECM. Look for a chalk-like formation, or worse yet, a green formation. If it is present, moisture has gotten inside. The terminals and rubber perimeter water seal will need a cleaning.
Light chalky corroded terminals cause increased resistance, then eventually a total disconnect. Injectors are very sensitive to increased resistance. They can shut down then recover in the early stages of corrosion failure, eventually staying dead.
Light chalky corroded terminals cause increased resistance, then eventually a total disconnect. Injectors are very sensitive to increased resistance. They can shut down then recover in the early stages of corrosion failure, eventually staying dead.
Last edited by Ron Dittmer; Oct 24, 2024 at 04:16 PM.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,411
Likes: 3,964
From: Cape Coral, Florida
2008 LS3 Automatic.
Bone stock.
Been experiencing an issue that I don't even know where to begin.
At steady state cruising - highway speeds; I start getting a periodic (for lack of a better term) misfire.
It honestly "feels" like the car does when the stability nannies kick in - like either fuel or spark is cut off for a split second.
Or if it was an older car; I would say the timing was off.
So it's just drive along fine and then the engine "bogs" then right back to running - the stutter is extremely short duration.
After it starts behaving this way - then it continues to stumble just slightly until I am finished driving - sometimes feeling like its about to stall when taking off from a stop.
I have changed plugs and wires - car normally idles fine.
Car has plenty of power (other than the stumble) - no CEL or codes.
I have had it throw a "Service Traction Control" on the DIC - but only momentarily and only when coming downhill on a reasonably steep mountain road.
I don't know if its fuel - spark - nannies or where to even start.
Bone stock.
Been experiencing an issue that I don't even know where to begin.
At steady state cruising - highway speeds; I start getting a periodic (for lack of a better term) misfire.
It honestly "feels" like the car does when the stability nannies kick in - like either fuel or spark is cut off for a split second.
Or if it was an older car; I would say the timing was off.
So it's just drive along fine and then the engine "bogs" then right back to running - the stutter is extremely short duration.
After it starts behaving this way - then it continues to stumble just slightly until I am finished driving - sometimes feeling like its about to stall when taking off from a stop.
I have changed plugs and wires - car normally idles fine.
Car has plenty of power (other than the stumble) - no CEL or codes.
I have had it throw a "Service Traction Control" on the DIC - but only momentarily and only when coming downhill on a reasonably steep mountain road.
I don't know if its fuel - spark - nannies or where to even start.
