Questions and Answers

Toyota Camry Engine Pinging Q. I have a 2000 Toyota Camry LE, V-6 engine, automatic transmission and 40,500 miles. Problem: When the weather gets warmer my car has a pinging noise (almost sounding like a 5 speed vehicle when it is about to die) when I accelerate from a stop or accelerate from a slow speed. It only last a couple of seconds. The hotter it gets the worse and longer the noise is.

I took it to my local Toyota dealership last summer and they advised that it was carbon build up and that it needed to be blown out. They told me to drive it on the highway and rev up the engine and to only use Plus or Supreme gas. As soon as the weather changed the noise stopped.

Now that it is getting hotter, the noise is back and louder than last year. I want to know if this true about the carbon build up or if it might be something else? Also, I want to know if this will damage the car in any way?

Thank you for your help.
Joy

A. Without hearing this noise, it is hard for me to know if it is engine pinging or some other type of noise.

If it is engine ping, or detonation, then it is possible it is being caused by carbon deposits inside the cylinder. It can also be caused by the incorrect spark plugs or ignition timing.

First, make sure you have the correct spark plugs. Toyota recommends NGK brand BKR6EKPB11 spark plugs gapped at 0.043". Ignition timing can not be adjusted, but it can, and should, be checked. If it is off it is an indication of a problem elsewhere in the engine control system.

Ignition timing should be 8° to 12° BTDC with a scan tool and terminals TE1 and E1 connected, at 700 rpm +/- 50 rpm.

If it is carbon buildup in the cylinders, then a good run at about 60 or 65 mph for 10 or 15 miles will clear it up. I think the quality of fuel is more important than the grade of fuel. You should use a name brand fuel such as Shell, Mobil, Sunoco or Exxon. You never know what you get from no name gas stations or independents. They buy cheap and sell high to make money.

Driving habits can cause excess carbon to build up as well. Short trips where the engine never gets to normal operating temperature will do it. As will sitting in stop and go traffic for long periods of time. You can get some GM Top Engine Cleaner from any GM dealer and use that to clean out carbon deposits. Just follow the label directions.