Hey guys i have 2007 Lexus ls460 140k miles which has a flashing yellow engine light. After attaching a scanner it gave us P0171 P0201 P0301 P2238 P2A00 C1201 these codes.



Upon inspection we did find few drops of oil in cylinder 1 spark plug so we changed the valve cover gasket, Spark plugs, & Ignition coils. It stopped the vibration and drives smooth.
but these codes still persist P0201 P0301 C120.



We have checked all the connections and they seem fine
anyone else faced the same problem before?
I need help and suggestions. thank you in advance

 

Here is all you have to know:

 

It tells you that there is an issue with one of injectors on cylinder 1. There are 2 in total.

 

Change all the vacuum hose.

 

vaccum hose was changed 6 months ago when I had a code for leak in the system. Rubber pipe had become brittle so I had that changed. We checked everything in the cylinder 1 but everything seems fine.

 

could it be an electric issue.?? I had a VSC code pop up every now and than but goes out in couple of days. Could it be the electric junction box on the pax side which is notorious for failing on this model. Now issue seems to be electric as its not getting enough electrical power. I’m exploring all options before going for injectors as they are extremely expensive. Thank you for ur time.

 

Are you saying that vacuum hoses would produce injector open circuit error code?

 

You need to figure which injector causes the error: port or direct. Port injectors are easy to remove, direct injectors are not so much.

I think, injector drivers have the same part number. Try swapping the drivers and see if the code moves to a different cylinder.

 

No, but can be a problem.

 

We will try to swap that as they sit on top of the engine. will update here.
My car went thru a pothole and all of this started. It’s not shaking as hard as it was before we changed the valve cover gasket and spark plugs.but it’s still shaking upon acceleration. I feel it’s something electric that shook up that day due to a pothole on the highway. I’ll try to swap the injector drivers and the fuse box to see which one solves the problem.

 

I didn’t know single cylinder misfire can turn my car into a hybrid

 

You know everything, you don't need help. Have a nice day.

 

thank you so much guys for all your help.

I was able to change the fuse box on the pax side and the battery which was causing the trouble. Now I have all codes gone except P0201. I have changed the spark plugs and coils on all of them. Now I’m planning to swap the injector driver to see if the code jumps to another cylinder. This all seems like an electric problem due to wrong size battery which was creating all these codes. Any other suggestions would be greatly appreciated. I’ll update here whatever happens.

 

alright I’m done with the swap and here are the new codes. From P0201 &P0301 it went to P0201 & P0205. Any insight?

 

Make sure you connected everything properly. If it is the case, it seems that one of the injector drivers is bad.

On other hand, P0201 remained. I would do compression test and visual inspection of the first cylinder. If that checks out, I think, port injectors are used during start up. It might indicate an issue with the first cylinder port injector.