I never experienced any sputtering problem with my 06 lexus gs300 until. I was exiting the freeway and from a full stop, my car sputtered. Can anyone give me an insight? Just changed the battery and when the incident happened I was low on fuel (30 mile range).

 

Maybe it's a transmission / torque converter issue. Try recreating it on a hill?

 

30 mile range shouldn't be a problem. 0 mile range would be a low fuel concern.

you could try to recreate it or wait until it throw an error code. I guess is it's this problem https://www.clublexus.com/forums/per...misfiring.html

 

First obvious clue would be fuel level, and sucking mixture of water (condensation) and fuel, or the fuel filter.
I'd fill it to the brim, with a good treatment like BG 44K, and drive it as recommended, topping up when 1/3 of the way through.
That'll clean the injectors and valves, and if the symptom doesn't reappear, then forget about it.
If it does whilst doing that, then it's something else - filter or spark plugs.
Speaking of them, if you've done 60K miles, they need replacing.

I highly doubt it is transmission related, as I would expect that to reappear - but don't rule it out entirely until you've done the basics first.
At this juncture, I wouldn't be pressing the panic button just yet.

 

Boron,

Are you saying that the fuel filter has to be replace at 60k??????

 

LADavidGS,

Did you resolve your problem? My 2006 GS just started doing something similar.
See my post below.

Car shut off while driving one day but didnt give any codes. Cranked it back up and drove it the next two days. Then it would not start at all the next day after I drove it to work. It tries to crank but acts like it's not getting fuel. Used engine start spray in the intake and it would start up but shut down once you stop the spray. Not sure if its the fuel pump, fuel filter, EFI, or a fuse. Has anyone seen this issue and/or know how to fix it?

It started up this morning, but ran a little rough at stop lights, so I'm thinking it's bad gas or fuel filter issue.


Need location of Fuel pump, fuel filter, EFI or the fuse if one of those is the issue. 2006 GS300

 

Not saying it has to be replaced, but it is an obvious area to have checked for blockage due to debris from the tank or deposited by the pump when filling up.
The Accord (TSX) was a fuel filter replacement recommendation every 25K miles - I've seen nothing about the GS in that regard, but can't see it not having one.

You're wanting to rule out obvious issues first, before worrying that it's something more serious.

 

Boron,

Thanks for the input. I need to figure out where the fuel filter is located.

 

I know I have the same problem. I am currently trying to fix a misfire on my lexus gs300 2006. The car sputters when your driving at around 1600 rpm, and when I first start the car on a cold start it sputters bad until the car warms up. When the car warms up it drives better but still sputters and by sputter I mean misfiring. The car also shakes when the cars rpm drops. I have a p0300 code which is random/multiple cylinder misfire, I have a p0304 which is cylinder 4 misfire, and p0306 code which is cylinder 6 misifre, and I sometimes get a cylinder 2 misfire. I also have a p0051 code which is oxygen sensor bank 2 sensor 1. I have changed the fuel injectors, the spark plugs, coil packs, crankshaft sensor and the camshaft sensor. Have any of you guys had this problem? and any advice?

 

Only the 2006 GS300 has carbon build up issues, the cause is that the injectors do not clean the intake valves.

You have changed many parts, the parts that you used to replace everything were they oem or denso brand?
I say that because there are many counterfeit aftermarket, so if you have the old parts it would be better for you and help diagnose the issue.

When you say you replaced the injectors, did you replace them yourself or did a shop do them for you? Did you replace them with cheap aftermarket? Which of the 12 fuel injectors did you replace was it the small secondary or the GDI? When you opened the intake manifold to replace the fuel injectors, did you guys look inside of the cylinder head ports to look for carbon buildup?

 

Sorry for the late response but the update is my car lost power to drive at all, so I changed my cats. I regained my power but the cat overheats, I assume its because the car is running lean and it misfires too. I know it is running lean and misfires because I have a autel scanner that gives me a in depth reading of the car and what the car is doing. On the scanner it says the car has a open loop fault, do you have any knowledge on why it could be a open loop fault, I haven't done much research on the open loop yet. My cat was also burned out on one bank of the 3gr fse engine. Also it the cat only overheats on one side and misfires on the same side which is the side with bank 2, 4, 6.

 

Remove the top and lower intake manifolds, (make sure to buy new gaskets) inspect inside of the intake head ports, you should be able to see down to the valves. Make sure all your intake valves are not clogged with carbon buildup/soot if they are then you can manually clean them with chemicals and long bristle brushes. Or pay to have it walnut blasted! Having intakes clogged would explain having poor air to fuel mixture, but more likely it would be rich instead of lean. Rich mixture or unburned fuel is what destroys catalytic convertors.

Your engine is known to have carbon issues, and if you are not on top of cleaning the carbon then it could clog the piston rings and then that will be super tough as the engine would burn oil. Removing the intake manifolds is not difficult, just a bit time consuming takes about an hour to remove or less

 

I took off the intake manifold and I see some black gunk on cylinder four, which is the cylinder that was misfiring. Do you know if that could mean this cylinder would need cleaning?

 

Shine a flash light inside the lower intake manifold, you should be able to see the valves. With oil on the intake maybe its time to put an oil catch can, and block off all the ports that the intakes sucks in from the valve cover or crank case. Maybe its oil entering the port and allowing the car to sputter, I would also remove all the fuel injector and clean them and install new oem o-rings.