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Check Engine light with VSC OFF light came on then within a minute car ran rough. Checked codes:
Disconnected battery to clear codes, car ran fine again for about 5 mi then happened again. Spark plugs replaced ~10k mi ago. It looks like the whole bank is misfiring... coil pack? Any ideas where to begin appreciated.
Since the DTC's point to the entire bank of cylinders, I would start the troubleshooting on something that is common to all. In this case, the most likely culprit is the black wire/connector (see circled in red below) that is shared among all the injectors on that bank.
If that's not it, I also attached the wiring schematic for the engine control system for your reference. Look for something shared by these cylinders.
Thank you for the response. Please forgive my ignorance, what component/part is that circled area part of?
Originally Posted by rkw77080
Since the DTC's point to the entire bank of cylinders, I would start the troubleshooting on something that is common to all. In this case, the most likely culprit is the black wire/connector (see circled in red below) that is shared among all the injectors on that bank.
If that's not it, I also attached the wiring schematic for the engine control system for your reference. Look for something shared by these cylinders.
You will find the "J6" connector in the engine bay near the ECM. See the electrical diagram below for approximate locations. As you can see on the electrical diagram in Post #3, the J6 connector distributes 12VDC power from the "INJ" fuse via the black wire of each of the injector connectors I9, I11, I13, and I15.
This happened to me not long after I got my LS430 with the spark plugs being replaced at similar mileage, the whole bank misfiring, and etc. After much trial and error, replacing 3 or 4 ignition coils solved the problem. Hope this helps!
I have a 2004 LS430 with 91K miles. After 7 weeks sitting in the garage, not surprisingly, I had to jump start it. However, shortly afterward, coincidental or not, "Engine" & "VSC off" dummy lights illuminated. Also noticed engine was running rough. I thought these problems may have been because I jump started it in the garage (on an angled surface). Moved car to level surface, disconnected the battery temporarily & then restarted it. Both lights reappeared after a few minutes and the idle became rough. Drove the car to Autozone to obtain fault codes. Notice idle was ok initially (for a couple of minutes) then rough. Car engine diagnostics showed P0303, Cylinder 3 misfire error code. Removed engine shroud & repair appears pretty straight forward. I will be isolating C3 misfire by swapping C3 coil with another cylinder (1 or 3). If it is the coil, I intend on purchasing the Denso OEM replacement. A pack of 8 are available on EBAY for $146. I'm wondering if I should replace all coils or at least the ones on the drivers side of the engine (which are easily accessible). Also wondering if I should replace the spark plugs while i am in there. Sorry for all the detail, but wanted to convey full situation. TIA, especially from folks who have had similar issue(s). Tx again.
I have a 2004 LS430 with 91K miles. After 7 weeks sitting in the garage, not surprisingly, I had to jump start it. However, shortly afterward, coincidental or not, "Engine" & "VSC off" dummy lights illuminated. Also noticed engine was running rough. I thought these problems may have been because I jump started it in the garage (on an angled surface). Moved car to level surface, disconnected the battery temporarily & then restarted it. Both lights reappeared after a few minutes and the idle became rough. Drove the car to Autozone to obtain fault codes. Notice idle was ok initially (for a couple of minutes) then rough. Car engine diagnostics showed P0303, Cylinder 3 misfire error code. Removed engine shroud & repair appears pretty straight forward. I will be isolating C3 misfire by swapping C3 coil with another cylinder (1 or 3). If it is the coil, I intend on purchasing the Denso OEM replacement. A pack of 8 are available on EBAY for $146. I'm wondering if I should replace all coils or at least the ones on the drivers side of the engine (which are easily accessible). Also wondering if I should replace the spark plugs while i am in there. Sorry for all the detail, but wanted to convey full situation. TIA, especially from folks who have had similar issue(s). Tx again.
UPDATE: Swapped coils and ruled out Cylinder 3 misfire is caused by a faulty direct ignition coil. Placed coil in Cylinder 3 into Cylinder 5, and coil in Cylinder 5 into Cylinder 3. Cylinder 5 operational and Cylinder 3 is not. Glad I didn't order the 8 pack of coils. Troubleshooting moving onto pulling & swapping the spark plugs. I hope the fault is being caused by a fouled spark plug, as I am not sure how to troubleshoot the connector wiring or have compression test tools. Any troubleshooting insight or feedback is greatly appreciated. TYIA
Does anyone use this forum anymore? I have been requesting some assistance with trouble shooting my 2004 LS430 for a Cylinder 3 misfire. I saw there was a ton of post about resetting the light, but not much on diagnosis of a real problem. Nevertheless, it was useful in getting me to this point of my troubleshooting. After verifying the ignitor coil was good, I have replaced the spark plug in Cylinder 3. The spark plug "looked" OK, but the engine appears to be idling normally with the new plug, i.e. no misfiring. Keeping my fingers crossed, the spark plug was the cause of the misfire. Although, the "Engine" & "VSC Off" light is still on. I am assuming I need to reset the dummy lights per 1 of the 2 procedures on how to reset the VSC light. I am wondering if I should use the updated 02 or 05 procedure. One person stated (& I would tend to agree), if you don't know which setting to jumper, you could cause more harm than good (screw things up). I am leaning toward the 2005 procedure but would really really appreciate some help form the people in the know. TIA.
Thank you.
After reading all of the post on sensor cleaning and use of fuel cleaner additives, I am of the opinion they probably don't apply to my situation. For my condition which exist in one specific cylinder with persistence, the problem is most likely a blocked fuel injector. Unless there is a FIY procedure on how to clear a blocked LS430 fuel injector, I am probably taking it to a mechanic. Thanks again,
If you believe it’s a block injector remove it call some shops around you and ask if they do injector cleaning they have a machine for it, if not than I would use a really good scan tool to narrow down the problem
Does anyone use this forum anymore? I have been requesting some assistance with trouble shooting my 2004 LS430 for a Cylinder 3 misfire. I saw there was a ton of post about resetting the light, but not much on diagnosis of a real problem. Nevertheless, it was useful in getting me to this point of my troubleshooting. After verifying the ignitor coil was good, I have replaced the spark plug in Cylinder 3. The spark plug "looked" OK, but the engine appears to be idling normally with the new plug, i.e. no misfiring. Keeping my fingers crossed, the spark plug was the cause of the misfire. Although, the "Engine" & "VSC Off" light is still on. I am assuming I need to reset the dummy lights per 1 of the 2 procedures on how to reset the VSC light. I am wondering if I should use the updated 02 or 05 procedure. One person stated (& I would tend to agree), if you don't know which setting to jumper, you could cause more harm than good (screw things up). I am leaning toward the 2005 procedure but would really really appreciate some help form the people in the know. TIA.
So in short your car is now running correctly yes? but the vsc light is still on?
is the question how to reset the the vsc light?.
If you don't feel comfortable with jumping the pins method then I would suggest buying a mini vci techstream cable assuming you have a computer handy. The cables are also useful for diagnosing problems with codes, sensor readings and changing default settings for various functions of the car.
If the problems are still present some sensor data like ltfts and any trouble codes present should help us help you.
VSC light and misfire
