Noisy Engine When Under Load

If you truly have pinging or detonation going on, the simplest thing to try is switching gasoline. Try a higher octane rating or even a different brand to see if it goes away. Outside of that, it could be anything from the valves needing adjustment, timing correction, or just a plain tune-up needed. Pinging is typically heard under load and more so in warmer weather. Pinging has a definite "clattering" sound.

Regards,

GK

It's a long shot, but my catalytic converter, when it first started it's death rattle, sounded enough like low-end noise (like when you lug the engine bad) to scare the bejeezus out of me.

-jeff

I tried running the higher octane fuel for one tankful, but got no results. I should have said that in the original post. Could it take a few tankfuls? Are those off-the-shelf "octane-booster" additives useful in this situation?

Also, I just read a couple articles on here about using a full can of carb-cleaner down the throttle body to rid the engine of carbon.. Is this a good idea?

It is not carb cleaner!!!

Carb cleaner will damage a TB unit, they make throttle body cleaners. if you check, you will find some that are designed to clean the TB and upper cylinder areas. You follow the directions and use the whole can.

A pint of ATF poured slowly down the throat of the TB while keeping it running with your hand on the throttle does the same job. That is also the directions for the can of cleaner. ATF makes a 'lot' of white smoke, but works excellently.

Lots of folks say a pint of water poured down the same way will also clean it good. That makes sense, if water leaks into a cylinder, the plug comes out clean like new.

Mike

Dave McGlynn wrote:

I have tried the water method. I used a spray bottle and shot about about a pint in it. after the last bit I idled the motor for about 30 sec. to a minute shut it down and let it sit for a minute. Started it up and gave it a good rev. Boy it belched out a carbon soot cloud and ran better after that. I like the cat. convert. idea too. I have heard the initial rattle of the unit failing. It was on a Dodge Dakota though, but still DC.