gs350lex

So i filled up my gas today and immediately after filling up and starting up the car i got a check engine light. I checked to see if the gas tank cap was on(tightened) and it was. So i decided to read the code to see what was going on. The car drives perfectly normally and idles fine as well.
I assume its just because of bad gas because I find it hard to believe anything could be really going on with the 02 sensors when the car only has 65,000 kms and is 4 years old. (Its a 2015 GS350 F-Sport).


Please share your thoughts thank you!

bclexus

There's no way that bad gas would throw a CEL code immediately after filling up with gas.

gs350lex

The CEL literally came on after filling up and pulling out the gas station so i assumed the two were related because there were no issues with how the car drove/idled. Any ideas what this could possibly be then because this worries me as the CEL on this car has never been triggered at all in the past.

Thanks

bclexus

It's hard to say because one of the more common CEL codes is for an O2 sensor to send data to the engine computer that triggers the CEL. It could be literally nothing, and just an anomaly that doesn't happen again. Or, after resetting the CEL code and it happens yet again, it could be the O2 sensor itself.

I personally would have the CEL reset and soon after make a half dozen WOT runs to redline (thru 2nd gear and upshift to 3rd gear) just to clear out any soot, moisture or carbon buildup out of the engine and the exhaust system ... and then see if the CEL code happens again.

gs350lex

I cleared the CEL and will try what you have suggested. I pray it doesn't come back but even if it does im sure my warranty will cover it (rather not have to replace something this early on but we'll see)

Thank you for your help i truly appreciate it��

update: took the car for a drive again did as you suggested CEL has not returned will have to watch it for a few days will keep you updated!

richard203

iTrader: (1)

if its under warranty why not bring ur car in?

gs350lex

I feel that if its nothing serious it would be a waste of time. It's out of the basic warranty but has extended warranty that should cover it. Also I have a feeling they would charge me to have it inspected and I don't want to waste time or money unless it is serious or I start to experience symptoms that would actually have me concerned. As of now there isn't a single symptom that would have me too worried aside from the CEL being on and it hasn't returned since being cleared (fingers crossed)

Thanks for your suggestion

bclexus

O2 sensors produce a voltage signal to the engine's computer based on the amount of oxygen in the exhaust system where the sensor is located. If the engine's air/fuel mixture is either too rich or too lean the sensor's voltage signal will be outside the normal range and therefore will cause the engine's computer to send the CEL. It doesn't take much deviation from the perfect air/fuel mixture to trigger the event. If the air/fuel mixture is off too much you will usually detect the engine not performing normally, which often is a surging or lackluster smoothness to the engine performance at most any rpm range or engine load. With today's fuel injection systems and engine management computers the air/fuel ratio is spot-on, so when a CEL code refers to the O2 sensor being responsible is quite often just a one-off oddity that is really not a problem at all, or a defective O2 sensor (which is not too common on a vehicle that is only a few years old). Using Tier 1 [recommended] Premium grade gasoline, keeping short trips to a minimum (where the engine never warms up to typical operating temperature), and every once in a while making a couple of WOT runs usually is all it takes to keep things happy.

gs350lex

As far as gas goes I only use Shell and 91 which is the highest available for shell gas stations near me. This car has generally been driven on long trips in the past but most recently within the last few months its been fairly short trips so perhaps this may have added to the CEL being triggered.

Anyways Thank you and i appreciate you taking the time to respond to me and shedding some light on this issue.

bclexus

Hopefully it was just an unexplained oddity that doesn't come back again. Let us know if the CEL returns.

kingofire

Make sure your gas cap is on tight. Sometimes loose gas caps can throw the 02 sensor codes.

EyeKutr

iTrader: (5)

I am with bclexus, drive it more WOT just to be sure....I do mine everyday

jessalynn

This has happened to me twice...once within a week of buying the car and I almost had a panic attack.

Tighten it up and give it a couple days and it will go away.

gs350lex

To address the posts above I always try to make sure the gas cap is tight (although that day after the CEL, i pulled over and tried to tightened the gas cap again). So far it hasn't returned(since i erased it) and I hope it doesn't return (praying lmao). Car drives great lets just hope it was nothing. Thanks for all the suggestions and help i will definitely let you all know if it returns.

gs350lex

Update: So an update it has returned a week later. I am still on the same tank of gas so I erased it and am going to watch it if comes back again I'll have it checked out and get to the bottom of this. Car drives fine, idles fine, not really sure how I could have an issue with the 02 sensor so early on in the car(a little over 4 years and 65,000kms). We'll have to wait and see