Hello,
My Lexus is idling roughly at start-up as well at stop lights. I put a scanner on my vehicle and two error codes appeared:
P0137
P0304

I re-set the codes and the check engine light has not re-appeared but the rough idle is still present.
Any help would be greatly appreciated,
Chris

 

A .5 second search on Google found this information.

http://engine-codes.com/search_codes...ar=P0304+LEXUS

http://engine-codes.com/p0137_lexus.html

 

Thanks for the smart-*** comment; I know what the codes are looking for solutions not URL's from members personal experiences

 

Did you recently put fuel in your vehicle?

Believe those to be O2 sensor and engine/cylinder misfire. Believe others can chime in with more complete information as to causes. If the problem just suddenly appeared, rough engine, then it could just be one tank of gas that needs treatment. If the problem has been gradually appearing over time you may need to consider cleaning the MAF as well as looking at the condition of those sensors.

 

I guess it was a bit sarcastic. But if your looking for advice on the Internet. And have a specific question. It would probably be a good idea to ask one.

Maybe something like this.

So yesterday morning my 2007 RX350 FWD with 41K miles. Doesn't start the first time I try. Works the second time. So ok.

On the way to work it seems like it doesn't have enough power. You have to step on the gas a little more.

I get home after work and cleaning Mass Air Flow Sensor. And I go ahead and change out the engine air filter.

Today I drive around town. And you can tell its not idling right. At the red light you can see the Tach drop for a second from 800 to 600.

Its not throwing any caution lights.

And ideas before I take it back to the dealer?


https://www.clublexus.com/forums/rx-...les-rough.html


You would have found this thread by doing a .5 second search on Clublexus

 

Update.
I took my vehicle to the dealer. The misfire fault code was still stored but the p0137 vanished. After a diagnosis and lengthy drive the misfire did not happen again. The ignition coils were switched from cylinder 4 to cylinder 2. Another test drive and no misfire. So we will see what happens and I will provide updates.
Has anyone run the Toyota fuel treatment through their system? Any feedback would be appreciated. I always run premium fuel and 90 percent of the time I use shell v-power

 

The P0137, which is an oxygen sensor code, would result from what occurred with the misfire, the P0304 code. Fuel doesn't combust right...well guess where that's going to be felt...any of the sensors downstream can be set off as a result. That P0137 is what I like to call an accompanying code because it got set off by something else and came along for the ride as a result.

Sometimes the misfires happen because of an issue with the gas, the air coming in, something with the voltage (even if the battery is fine). Sometimes the issue is temporary or it can be permanent and that vehicle will bog down. At least with my RX300, when that happens, the check engine light will flash.

Fuel injector cleaner can only help so much, that's usually used on other situations. My personal favorite though is the Redline Fuel System Cleaner (Pep Boys is where I see it at down here in terms of being sold in a store).

 

I just LOVE how these damn things stop acting up while @ the dealer! It`s like they know or something.

 

I don't blame anyone in this thread or anyone else for getting upset. These things can be extremely frustrating even for me and with an older vehicle, no matter how much I take care of it, I come to expect something will go amiss. The dealers do have all the tools at their disposal and will see these vehicles in and out every day. However, sometimes, things need to be road tested and it can be difficult to make something pop up. A freeze frame on an OBD2 or even a Toyota/Lexus diagnostic scanner can only tell you so much.

 

Sometime a little corrosion on the coil contact to the plug could be a culprit...I would have looked at the contact and made sure it is corrosion free and long enought to make firm contact with the plug...

 

I would reset the computer, disconnect the battery for an hour or so. That might help.

 

Update part II
After sitting in the cold for a few hours at the dealership, when I started my vehicle up the same symptoms appeared. I quickly summoned a technician. The problem was now a misfire on cylinder 2 which was the 'new' location of the ignition coil from cylinder 4. The ignition coil is the problem.
New ignition coil orders, as nothing is ever stocked anymore, everything should be back to normal on Monday
Thanks for everyone's help
Chris

 

Was a good way to diagnose the problem -- rotate coils and see if the problem moves with the change. Sounds like these guys are on the ball.

 

Chris, how many miles on your car? My 05 needed a coil at 73k.

 

Hi Carver,
My RX has 160000 km which is just shy of 100 000 miles
Chris