Engine Pinging

[Eagle]

My 99 RX300 (FWD) with 58K miles has recently developed engine pinging. At first I thought it was bad gas (the vehicle uses mid-grade fuel). But now after several tanks of different mid-grade fuel AND a couple of tanks of premium, the pinging is getting worse. Accelerating or driving up a slope just sounds awful. I am scheduled for a service this coming week for this problem. If anyone has any pointers or thoughts on this, I would appreciate it.

[SKperformance]

get a motor vac engine fuel flush

change your spark plugs

and hope the belt has not skipped causing the timing to be out

[SW03ES]

And also, the engine is actually designed for nothing lower than 91 octane, thats premium gas not mid grade. Mid grade is usually 89.

[Eagle]

Thanks for the hints for resolving the pinging problem I was having. Fortunately, the problem did not stem from anything major. The dealer believed the problem to be from several sources:

1 - The gas in the NorthWest (I live in Oregon) is considered poor in quality overall unless bought from one the majors like Chevron or Texaco. Though I bought gas from another major on two occasions, who "shall" remain nameless, this is where I first noticed my problem.

2 - The fuel injectors were very dirty.

3 - The fuel throttle body(?) was also very dirty.

4 - The air filter element was also very dirty.

Though my driving habits or areas driven have not changed and I have had all regular dealer services, the gas quality explains alot since I moved to this area recently. The dealer also suggested, that even though my 99 year model operates on mid-grade fuel, that I use premium fuel.

[SW03ES]

The fuel injectors and the throttle body being dirty were caused by running too low an octane gas, use only premium in the future to keep that from happening. I always use Exxon, mostly because I have a Speedpass thingy and have never had any problems.

[huylanalexus]

Thanks for the hints for resolving the pinging problem I was having. Fortunately, the problem did not stem from anything major. The dealer believed the problem to be from several sources:

1 - The gas in the NorthWest (I live in Oregon) is considered poor in quality overall unless bought from one the majors like Chevron or Texaco. Though I bought gas from another major on two occasions, who "shall" remain nameless, this is where I first noticed my problem.

2 - The fuel injectors were very dirty.

3 - The fuel throttle body(?) was also very dirty.

4 - The air filter element was also very dirty.

Though my driving habits or areas driven have not changed and I have had all regular dealer services, the gas quality explains alot since I moved to this area recently. The dealer also suggested, that even though my 99 year model operates on mid-grade fuel, that I use premium fuel.

Hi Eagle and everyone-

How do you clean the fuel injectors and fuel throttle body? Please provide me more detail, i want to do this service for my car.

thanks

[tmastres]

And also, the engine is actually designed for nothing lower than 91 octane, thats premium gas not mid grade. Mid grade is usually 89.

Holy Smokes Batman where'd the hell did you get that!! I've Always used 87 gas and never had a problem as have many others here and NOWHERE in my Lexus owners manual does it say use premium fuel of any sort (other than stating 91 Research octane) which is esentially 87 as we measue it here in the US. Sorry man, just don't buy that! Ther MAY be some truth to there being other junk inthe gas from cheapo gas sources, who knows you certainly can't state it as so unequivocally, but the use of premium has been debated here so often it isnt worth doing again. You simply cannot state this as fact.

In case you dont believe me "select octane rating of 87 or higher" direct quote form the owners manual It does go on to say that you MAY get better performance form higher octane fuel but it is not required. I've found there's no difference in my driving experience with either 91 or 92 octane fuels.