We have a 2015 RX350 with 98K miles on it. Has recurring P0303 code with CEL, VSC, Trac Off lights. Previous 1st owner had an IL Lexus dealer disassemble the engine, swap coils and add a new fuel injector to no avail - they then traded it in (we're assuming) and the car was sent to the auto auction. We came along unsuspectingly and bought this car as a 2nd owner from a small dealer who didn't disclose anything to us. The CarFax didn't have the engine dismantled data on it - just had standard maintenance records. We've replaced coils/spark plugs and spent a lot of $ and problem is not fixed. Car seems to drive fine - no issues; but won't pass emissions and we can't use the cruise control. Plus, are we damaging it further by driving it?

Local WI Lexus dealer also said that they can't fix it, as the engine was already dismantled and they wouldn't know what to do next. They actually told us "we don't recommend further repairs".

Lexus corporate won't help us as we've contacted them.

Any ideas???

 

Did you talk to the dealer that did this repair? Maybe they can help you. When I pulled the repair maintenance history on my RX from Lexus Owners I was amazed that half of that didn't show up on Carfax.

 

Trying to follow your story. It appears the dealer who sold it to you bought it at the auction where the Lexus dealer unloaded it after they could not fix it. Later on when it failed emissions and had codes you somehow discovered the sordid history of this vehicle. When did the codes show up after you got it?

The original Lexus dealer probably did not disclose the problems and maybe the guys who sold it to you were unaware of them as you said it drives okay. Or they cleared the codes. You probably won't hurt it by driving it more. You may want to find a great independent Toyota/Lexus specialist to analyze & diagnose your problems before taking the next step which would be to........

Trade it in for another car. Do not waste any more money trying to fix it. Take your loss and get another vehicle. That it may need an engine rebuild that will cost more than the car is a great reason to trade it in.

Lexus corporate will not talk to you because there is no longer any warranty on the vehicle and you are not the original owner.

Next time you want a Lexus or Toyota you can join the Lexus Drivers site or Toyota Owners site and enter the VIN of the vehicle you are interested in and it will show you its dealer service history. CarFax cannot provide all of this information as it focuses on accidents and general service such as emissions tests. You should check the history of the lemon you just bought.
https://drivers.lexus.com/lexusdrivers/

https://www.toyota.com/owners/my-veh...E&gclsrc=aw.ds

 

But assuming the OP did go on the Lexus Owners site and found out that work was done on the engine, etc, wouldn't it actually tilt his decision in favor of buying the car knowing that a Lexus dealer had performed the repairs and not some fly by night shop?
(Unless of course the Lexus dealer said in their conclusion that they couldn't fix the issue.)

 

I think after he got it and had a check engine light he called the dealer that serviced it and that was identified on the Lexus Owners site records. I think if he checked the LOS before buying it then he assumed the dealer had properly repaired it. I am surprised they have not told him what is actually wrong with the engine. It must be really bad.

 

True. If they performed the work then they should give the OP the outcome of that work performed.

 

We have not gone back to the IL Lexus dealer that fixed it - they changed hands to a new dealership so we weren't sure who to contact. We called our local WI Lexus dealer who easily found the sordid car repair history and told us "We would not recommend any further repairs. They did all that they could do. Try Lexus corporate". They also couldn't believe that we weren't aware of all that was done to the vehicle.

 

What's so unbelievable that you didn't know the repair history? Most buyers are made to believe that a Carfax report is the bees knees. Not all Lexus buyers are aware of the Lexus drivers website.
Could your WI dealer tell you the outcome of that repair? What was the outcome of the repair performed by the Lexus dealer? You deserve to know that.

 

This just came to my mind. When you bought the car, had it been smog tested? My car had to go through a smog test to get the current registration.

 

Not enough info here, but it is early for me so maybe I missed some. Is the code persistent or intermittent (and how often)? Does it recur under certain conditions or random conditions? Is the CEL flashing or solid, or is it some of both? Does it present any drivability issues at all? Was there any other services performed just prior or at the same time as the IL dealer repairs? Has a tech at your dealer looked at it, or are you going off the words of a service advisor that recommended no further repairs?

Based of these answers, I would hazard a few guesses. First of which is to say that cylinder 3 is in the back, by the firewall behind the intake manifold, and it's a PITA to work on - your dealer probably just doesn't want to deal with it. A good independent shop might be more willing to take on the challenge, but of course there is no guarantee that they'd be skilled enough to find it either.

1) P0303 is misfire in cylinder 3. If it is a coil/plug issue, it would be a flashing CEL, which would indicate that you are doing some extra damage driving it around like this. Fuel is getting in but not burning due to no spark. That fuel is making it into the catalytic converter in extreme amounts, which could be burning it up.

2) But a flashing CEL is usually accompanied by serious drivability problems, like very rough idle and very low power. If it isn't anything like this, and the CEL is solid, that would indicate no fuel. Being that the fuel injector has been replaced, it could still be a wiring issue that is causing the injector not to fire. Or perhaps the fuel rail happens to be plugged right there - not so sure about this possibility, haven't played with fuel rails enough to know if it's possible for pluggage to occur and/or for it to only affect this one cylinder.

3) Another possibility, especially if the spark plugs were replaced just prior to the original repair, is that the intake manifold was not resealed properly (o-ring gasket at each intake port) and is pulling extra air into this particular cylinder, which could cause a misfire. Even if the plugs weren't replaced recently, the plastic intake manifold could still have an odd crack in it causing this issue - Sandi_K had an issue with their intake manifold, although that vehicle had 240k miles on it.

4) other more haphazard, less likely guesses: valve stuck open or closed? Perhaps broken valve spring, worn camshaft (this was problematic early in the 2GR life). Bad rings in the cylinder (no compression = no combustion = misfire). Bad fuel? If the car drives mostly normal, I would go here first - try a few tanks of 91 or 93 octane from another station. I doubt this is a case of bad fuel, but you never know. Based on how mild the symptoms are, I might even hazard a guess of a MAF or O2 sensor just starting to go bad, but those issues usually don't present themselves like this. Those would be the last things I change before trading the car, although I've cleaned MAF sensors successfully in the past for $10, so that might be worth a shot

Again, the likelihood of any of my above guesses goes up and down with how the car is actually behaving. And I do realize some of them are wayyyy out there (particularly in #4). But I just wanted to give you an idea of how much more stuff could be checked - maybe some of it has been already and just not mentioned or not connected with this issue. Good luck, keep us updated.

 

you still have this problem?

 

Rodents chewed the wires? Seems to annoyingly common