Hi. I just got this Lexus ES300 2003 from a used car shop about a month ago and it ran perfectly fine until the engine shut off on me and my friends as we exited a highway. It blew steam and I ended up having to get the water pump fixed as well as the power steering as it had been acting up for a bit. Quite a hefty purchase! Anyways, as soon as I got it back from my mechanic I was driving home and noticed the engine would shake as I idled and when I would accelerate to a certain degree. I took it to autozone and had it scanned, cylinder 3 misfire, I figured it was the spark plugs at first so I took on the (horrible) task of replacing them and quickly found they were not the issue. So I replaced the ignition coil today and it ran perfectly fine for around 5 minutes, the length of time I tested it for.

A little context, when I would drive with it beforehand it would speed up to about 20 mph then shift to second, after this it would stay at around 3000 rpm and wouldn't go anywhere past it. After replacing the ignition coil it didn't do this anymore and ran just as it had when I bought it.

Until I turned it on for the second time of course! The cylinder is definitely firing now as the engine does not shake when idling and my mpg are about twice what they were. However, it now drives exactly the same as it had before, and the check engine light still came on.

I took it to Autozone to have them check the codes and to my surprise nothing showed up. So I thought it was a glitch where it kept putting it in limp mode and I reset the codes by putting the two battery terminals together for a little while as directed by an Autozone person. Still, nothing. No codes and no glitch? After doing some searching I came up with it maybe being a shift solenoid issue. I haven't done much research on it yet so I have no idea where in the engine it is or how to diagnose it, but I was wonder if this sounded like the solenoid to anyone else and if with all the backstory I provided if any of that could have caused this to happen in some shape or form.

Any ideas?

 

I have had issues with those solenoids but they have thrown codes so it was easy to diagnose. Never had exactly the symptoms you described. There are like three different solenoids. They are all in the upper valve body. It is a pain to get to them but it can be done with patience and organization. You have to remove a lot of bolts and tubes. You might not have to go through all that to check them though. They all lead back to the ECM where you might be able to test them from. But I never did that since mine threw codes.

 

Did you get the issue resolved?