toyhauler

I don't know why this is happening. The Check Engine Light is not on. If I use hi octane fuel, the pinging stops. This vehicle should run okay on regular shouldn't it? This seems to be a recent problem, but I don't know why.
If anyone has any ideas, please let me know.
Thanks,
Ron

salimshah

With engine cold pop open the radiator and see if the coolant is full. Also check reservoir. Run heat for couple of minutes when engine is hot and recheck reservoir.

Next item would be the air filter.

Beyond these, you will have to make a trip to the dealer/trusted-mechanic.

Salim

Fern

Next time you get tank filled with Premium and get home.

Turn engine off and diconnect the EFI fuse in the engine compartment, I believe its fuse #13 (this will reset the ECU).

Leave fuse out for about 5 minutes.

When you re-install the fuse and then start up the car, you should not get the pinging again.

Had the same problem with my '99 despite using premium fuel.

Once I reset ECU, pinging went away and I have been using mid-grade ever since...

BTW mid grade gives me MUCH better/ smoooother trani shifts..
Try it out and let us know results.

Fern

Lexmex

Sharing south of the border experience,

Often times, my track runs won't be very pretty and the injectors will make a lot more noise than usual. Even though I run 92 Octane, the gas here is still loaded with more sulfur content than that found in the U.S. and I have no idea what other chemical impurities, but it never runs as well as back in the U.S., even when I am sea level places like Acapulco or Veracruz.

I then use a good quality fuel injector cleaner like Techron and/or Restore and the times get back up to snuff plus the injectors are quieter.

One good side effect of having higher sulfur is that the engine will run a little cooler.

toyhauler

Thanks everyone. I shall try everything you have suggested. I really appreciate your responses.
Ron

salimshah

Please do post, what worked and what did not.

Salim

ravengotu

But only when i put mid grade or lower octane.....you said no engine light...mine comes on as well with the pinging

Lexmex

That's probably a function of a rich/lean error, most likely a lean one.

toy4two

get some BG 44k or get professional cleaning down.

Lexmex

What can happen using lower octane is that the burn is not crisp and there is some oxygen left over detected by the O2 sensors, causing the light. For as bad as the gas is down here, that happens when my injectors get clogged (just about every month I have to use Techron).

Fern

Hey toyhauler,

you mention the pinging is just a recent problem.

Whats the mileage of the vehicle and the condition of the emission control devise, ie: egr, o2 sensors, etc.

Has timing belt been changed recently?

The pinging may be due to a faulty knock sensor or possibly an EGR valve that is malfunctioning. Also, the timing belt being off a tooth or two could also cause this.

Either way pinging is not normal and should be looked after.

HarrierAWD

Since the pinging stops with high octane fuel, you may have carbon deposit somewhere in the combustion chamber. Most likely on top of the pistons. The deposit reduces the size of the chamber and cause the regular gasoline to "pre-detonate." Thus the pinging or knocking.

You can try adding a bottle of B-12 Chemtool to your gas tank, available at AutoZone. It worked for my GM car. Don't bother with Techron or STP stuff, they are just "feel good" products. Don't try oil additives, either. They don't get to the combustion chamber.

Next try would be GM's Tops engine cleaner (don't think Toyota makes anything like that.) Remove all spark plugs and pour the stuff in. Let it soak overnight. Put a towel on the engine and crank it to get as much gunk out as you can. Put the plugs back in and run the engine. Be warned that your tailpipe will smoke like a Marlboro Man for 10 minutes.

If it gets bad enough, you'll have to take it to the dealer. They'll have to take the engine apart to clean off the deposit.