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Need help on this forum. My 2001 LS430 has check engine and VSC OFF light on, and Diag with OBD-II scanner showed error code of P1349, P0303/P0301/P0307/P0305 which are cylinder 3/1/7/5 Misfire Detected. I bought spark plug (NGK IFR6T11) and Coil Pack from Amazon, and have replaced both spark plug and coil pack for #1/3/5/7. However, the problem didn't get fixed. Any idea what's the problem and what additional I need to fix?
Thanks in advance!
Did you clear the codes and have the reappear? Were you cautious with the COP plug removal? As others have posted, if you use the wrong method you'll pull the wires out of the harness. Did you use OEM Denso COPs? Did you get authentic parts? Lots of fake parts on Amazon and eBay, have to be VERY cautious when purchasing.
I'm not sure of the cylinder order, but if they are all on one bank, you might have a problem with the main signal going to the COPs for that bank.
Also, did you address the P1349 VVT issue?
Did you clear the codes and have the reappear? Were you cautious with the COP plug removal? As others have posted, if you use the wrong method you'll pull the wires out of the harness. Did you use OEM Denso COPs? Did you get authentic parts? Lots of fake parts on Amazon and eBay, have to be VERY cautious when purchasing.
I'm not sure of the cylinder order, but if they are all on one bank, you might have a problem with the main signal going to the COPs for that bank.
Also, did you address the P1349 VVT issue?
Yes, I cleared the code and they reappeared.
Yes, I removed COP cautiously, and all the wires are fine.
For parts, not sure if they are authentic, both spark plugs and COPs were bought from Amazon.
All cylinders reporting the error code (1/3/5/7) are in driver side, and I have the same doubt as you on the signal but don't know how to further diagnose it.
Didn't address P1349 yet, was hoping to get P0300 fixed first, then search for ways to fix P1349.
Here is a copy of the factory service manual, though I'm not sure what year your vehicle is. https://cardiagn.com/lexus-ls-430-20...repair-manual/
I'm not sure but perhaps each bank has a fuse for the COPs on that bank... might be something to look at since the whole driver's side bank is affected.
The vehicle does run though right, even with the codes? If it does, is it smooth, or is it undriveable? You could have a broken wire somewhere that feeds the driver's side bank.
Here is a copy of the factory service manual, though I'm not sure what year your vehicle is. https://cardiagn.com/lexus-ls-430-20...repair-manual/
I'm not sure but perhaps each bank has a fuse for the COPs on that bank... might be something to look at since the whole driver's side bank is affected.
The vehicle does run though right, even with the codes? If it does, is it smooth, or is it undriveable? You could have a broken wire somewhere that feeds the driver's side bank.
Thank you so much!
It's 2001 LS430, and I can still drive it smoothly. It shakes a little when stopped at traffic light, with check engine and VSC OFF light always on.
Thank you so much!
It's 2001 LS430, and I can still drive it smoothly. It shakes a little when stopped at traffic light, with check engine and VSC OFF light always on.
Originally Posted by Romanova
Here is a copy of the factory service manual, though I'm not sure what year your vehicle is. https://cardiagn.com/lexus-ls-430-20...repair-manual/
I'm not sure but perhaps each bank has a fuse for the COPs on that bank... might be something to look at since the whole driver's side bank is affected.
The vehicle does run though right, even with the codes? If it does, is it smooth, or is it undriveable? You could have a broken wire somewhere that feeds the driver's side bank.
Hi Romanova, your repair manual is really helpful! Thanks!
I looked at Ignition System, and the circuit diagram on page 2 is useful. It clearly shows the common thing among cylinder#1/3/5/7 is the #1 connector on each spark plug, which connect to a Noise Filter (N1). Same for #2/4/6/8 connects to N2. So I swapped N1 and N2 to try to see if Misfire code will move to #2/4/6/8. However, there are no more Misfire error codes after driving ~20 miles (before the error returned quickly). The engine is quite, and there is no more tremble/shock from engine. The only error now is P1349 (attached). What's possibly wrong and any idea how to fix it?
You probably need a new oil control valve. I believe each bank has one. I would go OEM for the replacement.
I don't know if that will actually fix it so do more research before you throw parts at it.
Edit, looks like OEM is about $65 each. Make sure you buy from a trusted supplier and AVOID Chinese garbage. Looks like they have a separate filter element, replace that too if you do it.
Thanks for the help! And here is my update to confirm that did fix the problem.
I bought a pair of SKP OCV for ~$80 from RockAuto.com. And I just replaced the left one (as the code indicated). The problem was fixed and the car has no problem since then running 100 miles/day for over 3 weeks.
This forum really helps!
Originally Posted by Romanova
You Google the code yet? Check this video https://www.youtube.com/watch?v=Nm25CP_SsIA You probably need a new oil control valve. I believe each bank has one. I would go OEM for the replacement.
I don't know if that will actually fix it so do more research before you throw parts at it.
Edit, looks like OEM is about $65 each. Make sure you buy from a trusted supplier and AVOID Chinese garbage. Looks like they have a separate filter element, replace that too if you do it.
Thanks for the help! And here is my update to confirm that did fix the problem.
I bought a pair of SKP OCV for ~$80 from RockAuto.com. And I just replaced the left one (as the code indicated). The problem was fixed and the car has no problem since then running 100 miles/day for over 3 weeks.
This forum really helps!
With BMWs folks routinely swap them to see if the code follows, and that usually flushes out which VANOS solenoid is bad. Seems like there are so many similarities between vehicles, one brand calls it A, another calls it Z, but they do the same thing....knock on wood I appreciate the simplicity of our engines, so much can be DIY! good job!
Helpful thread. The pictures are long gone but the description was plenty good. My only surprise was just how deep the darn plug holes are.
That went really well. Wow, a LOT easier than when I changed the plugs on my Ford Expedition. That was a real chore.
I realized after I had everything back together I should have taken a few pictures. D'oh. So much for public service. But here's my original (I think) plugs with 113,000 mi on them.
You Google the code yet? Check this video https://www.youtube.com/watch?v=Nm25CP_SsIA You probably need a new oil control valve. I believe each bank has one. I would go OEM for the replacement.
I don't know if that will actually fix it so do more research before you throw parts at it.
Edit, looks like OEM is about $65 each. Make sure you buy from a trusted supplier and AVOID Chinese garbage. Looks like they have a separate filter element, replace that too if you do it.
Anyone knows where is the oil control valve located on our engine ?
Helpful thread. The pictures are long gone but the description was plenty good. My only surprise was just how deep the darn plug holes are.
That went really well. Wow, a LOT easier than when I changed the plugs on my Ford Expedition. That was a real chore.
I realized after I had everything back together I should have taken a few pictures. D'oh. So much for public service. But here's my original (I think) plugs with 113,000 mi on them.
What brand of the plugs did you end up using it ? Link please lol
02-23-19, 10:56 PM
