Naraham

Good morning Club Lexus

I have a 2000 RX300. Friday I filled up as normal and decided to use Cheveron Techron Concentrate to try to improve my gas mileage. Ok that was Friday. Drove the car for a short distance Friday and by Sunday I had a CEL and bad ideling some sputtering . Got the codes ran at local AUTOZONE. Sunday it said that it was due to bad Carbon canister. Which I have to admit, the pump that I was at didnt automatically stop. i stopped it when I heard the fuel getting close to the rim. SO I could have gotten a little fuel in the Carbon canister. (understandable) I didnt smell fuel then.

Today while driving I am getting a flashing CEL. I smell fuel so I took it back to have the codes read again. This time I had multiple misfires on cylinders 1,3, and 5. Not to mention that I have no overdrive. Of course it was recommended that I get new spark plugs, but I am not quite sold that plugs are the problem nor the solution. Has anyone else had this issue? I hoping that I can just run this gas out of my vehicle and everything will go back to normal. What do you think?
Thanks in advance!!!!

carguy07

I seriously doubt it has anything to do with the Techron, probably just a coincidence.

salimshah

First a warm welcome.

Out of curiosity did you read the sticky before posting? https://www.clublexus.com/forums/rx-...a-problem.html

Salim

Lexspeed

Yep, I agree completely. It was a coincidence. Look elsewhere for the culprit.

jbl-1985

x2 - I've used Techron Concentrate for years without incident and results have always been positive.

CharBaby

My wife's '01 RX throws a CEL/VSC light almost each time I have put in any Fuel System Cleaner(FSC) whether it's Techron or Regane or even MMO.

It has done this since new although, when the CEL comes on, the engine still runs well.

I have checked the Code#'s when the CEL/VSC lights apear and it pertains to one of the A/F sensors.
If I clear the code(battery disconnect or remove the ECU-B/EFI fuses) and the lights disappear, they will often not appear again.

A fresh tank of gas and all is well til the next dose of FSC. I have replaced all of the A/F and O2 sensors over the last 12 years as they finaly did go bad(a known RX issue according to some reports) and no amount of Code Clearing would make the CEL's dissappear. I have also replaced 2 of 3 catalitic converters as they too rusted out at the pipes and required replacing as no shop will fix/weld/patch the pipes on converters.

I still have this issue with the CEL/VSC when adding FSC so, I don't do it often A lesser dose than required WON'T throw a code(CEL/VSC) so, I'll sometime only add a little, maybe 1/2-3/4 of the doseage

code58

I s I use it in my wife's Camry's (current and former) as well as my Ford F-150 and have never had a CEL either with the Concentrate or the injector cleaner. Excellent product!

LA4Mead

I use Techron concentrate with no problem, owned my RX since 5/98 new. What's in your local fuel mix may be different, but still doubtful it's the fuel system cleaner. My A/F sensors lasted longer than ususal compared to any other vehicle I've owned (one tested bad over 130,000 miles just replaced them all as one set)... I'm guessing you've got other problems to address.
Could the misfires be due to fuel problems upstream?

bgqkeneg

I seriously doubt it has anything to do with the Techron

Lexmex

Any cleaner used can clean something out and you might get a code initially as a result. That's just the cleaner doing it's job, not the cleaner causing the code itself. I had this kind of issue in Mexico, but the end result was a better running engine afterward.

CharBaby

Exactly! I don't have this issue with any of the other vehicles, only my wifes RX and it doesn't seem to matter which product I use(Techron, Regane, MMO, SeaFoam etc.). But as I stated, if I use a lesser doseage than the directions state, the RX won't trigger a CEL.

LA4Mead

I've used two bottles of Techron and other cleaners like Lucas in more concentrated doses... and never had CEL codes from using cleaners in the fuel in the RX300. Codes do appear when spray cleaning through the throttle body with CRC with the engine running (as expected) but then I ignore those and reset the system.

I haven't had problems with the same components you mentioned; the cannister, cats, etc. Maybe there's something to those that will help to diagnose the problem, but I'm stumped why the misfires?

Have the plugs ever been changed? If they have never been changed and you don't regularly use fuel system cleaners or perform EFI cleaning, there is a chance you may have one or more fouled plugs. The rear plugs are no fun to replace. I had mine replaced at the Toyota dealer at 120,000 miles. Hardly a diagnosis, but something to consider.

hypervish

I've run various different cleaners through the gas, and haven't triggered any CEL's over the years.

1sWt2GS

iTrader: (6)

i highly doubt gas caused a CEL

Naraham

***update*****

Good morning club Lexus.

Ok. So after posting my initial problem, I had all the plugs replaced. Just as I thought, no fix. My old plugs where still good, but I replaced them all to rules out the plugs. Now, prior to using the Techron, I had just replaced my bank 2 VVT solenoid. Which from my understanding had something to do with plugs 2,4,6 or maybe the other way around(1,3,5). Nonetheless, my car still ran horribly. The only benfit so far was that my CEL wsn't flashing anymore, but I am easily annoyed but lights being on. So I took it back to AutoZone had the codes read again and what do you know this time I got a 1349 code indicating that my bank 1 is going south. So I'm having it replaced as I type. Hopefully this will be my fix. Will update when I get my baby back!