divertom64

took my rx300 2000 to the dealer and they checked it out and no codes they did a little adjustment for the timing but still pings/rattles.. up hill loads at any speed.. then I took it to the auto part store to have them do the code readings and still PASS no codes.. the Lexus has around 109k miles on it... ok now we just bought the car like 4 months ago.. and we have been putting regular unleaded in it for about 2-3 tanks worth.. then we found out it takes premium so we been using Chevron premium and still pings. other than that car runs great.. The dealer dont know what to say. auto part store said try replacing the feul filter,,, HELP!

salimshah

I noticed a difference after I changed my knock sensors, but I waited till I got knock sensor code.

Also try replacing spark plugs around 110k.

Salim

maxSteel

I have only used regular in my 1999 rx300.

Don't know why a fuel filter would make a difference.

How is the engine temperature? Have you tried gas from other stations?

divertom64

in the manual is says to use premium gas 92 octane... and the dealer also told us too... Maybe its time to change the spark plugs I will try that should i just stick with the oem type or ? the knock sensor was replaced when we bought the car.. still no codes...

salimshah

Were all knock sensors replaced or just the ones that showed a code?
For plugs, I would say stay with OEM.

Salim

rx300mm

fyi, I have only used 87, regular gas for last 7 yrs and no issues.

divertom64

how many knock sensors are they? I believe the dealer only replaced only one... but after testing all code pass.... retested at the dealer and a second opinion at a auto part store both pass... still knocks I think I will try Oem plugs first then try other gas stations gas..

maxSteel

My manual inside back cover says:
"Select Octane Rating 87 (Research Octane Rating 91) or higher. For improved vehicle performance, the use of premium unleaded gasoline with an Octane Rating 91 (Research Octane Number 96) or higher is recommended".

I just use regular (87 octane).

jmezo

Try this:
Change the oil. If the problem goes away but then comes in back 2-300 miles then you need to do the autoRX oil treatment.

code58

Tom, how did the dealer adjust the timing? I wasn't aware there was any way to adjust the timing on current cars, it's all done by the computer. You certainly don't have a distributor to adjust. I also thought there were 2 knock sensors. IF there are and they only replaced one, maybe that's the problem. It's quite a bit of work to replace, are you SURE they replaced even one??? The car doesn't NEED anything but 87 octane. The computer makes the adjustments. My DIL's RX has over 150K mi. on it, ALL on 87 octane with nary a ping of any kind. You DO realize that a "spark knock" is NOT good for the engine! I have read on this very forum a post by someone asking about heavy pinging and I said DO NOT DRIVE that way and his next post was that the engine had blown up on him. That's as in NO KIDDING! A light ping may not be destructive, but a heavy pinging definitely can a will be! And BTW, I have my serious doubt that it even needs plugs, the original are Iridium and last forever and would not likely be the cause of pinging anyway.
2 additional things- I would seriously question the competency of the mechanics at that dealership. Is it a Lexus dealer? 2nd, don't go to the auto parts store for your diagnosis. If they told you it might be the fuel filter causing the ping, don't walk, RUN from there. They are clueless!

hypervish

It's true the iridium plugs that came with the car can probably last as long as the car. I replaced mine just last month, at 160k and the plugs looked like new. That doesn't mean that the spark was good as new, or electrode but they looked great.

salimshah

Recommended spark plug replacement is at 110K miles. I overlooked it and one plug died at about 130k+ miles.

Salim

code58

Salim, You did give it proper burial didn't you? Gasp! I hope you didn't just throw it in the trash can. Any plug that serves faithfully for 130k mi. deserves better. Just think how small a grave and how little time to dig... Do the right thing.

salimshah

All six were thrown in the recycle bin and stayed together while they were in my sight. Usually I stay on top of recommended maint, and incorrectly assumed they were replaced at 90k service. When one failed, I called the service dept and was told that "no the plugs are to be replaced at 110k". After doing one transverse mounted TB replacement, I give money to the mechanics. Not worth the aggravation .

Salim

divertom64

OK guys thanks for all the info I am going to take this Lexus to a shop and there gonna do a full diagnoses computer check, not like the free one it has been done on it... the kind it cost alot to do... then I will get back you let ya know whats wrong...