Pinging Under Load

Hi All...

We have a 2000 Accent 5spd with 150k on it that pings quite a lot under
load. This has been gradually getting worse. Any ideas what could be causing
this problem?

Steve

 

With that kind of mileage, I would suspect carbon buildup in the
cylinders. Then again, it could be a timing issue. It could also be
spark plug related. When was the last time you changed your plugs?

 

Hi there..

Plugs were changed about 5k ago and the old ones were good colour.
Timing is good as well but I was wondering if this could be an anit-knock
sensor or something to do with the cam position sensor? Would this prevent
timing from being advanced etc?

Steve

 

This vehicle is equipped with a knock sensor. If it does not operate
properly and the computer does not discover this, it may overadvance the
timing.

You should be using 87 Octane fuel or better. Lower than that can cause
spark knock.

Anything that will increase combustion chamber temperatures or compression
(including carbon build-up) can cause spark knock.

 

Hi Hyundaitech,

Thanks for the response. We've been using 91 octane for the last couple
of years now and that cured the problem then but it's quite noticeable now.
There are no codes set in the computer (just read it) and is starts fine.
Any way to check the knock sensor?

Steve

 

Ironically, that may have contributed to the problem. If you use 91
octane fuel in an engine designed for 87 octane, it doesn't burn
efficiently and leaves more deposits in the engine.

 

You could try tapping on the block near the sensor with a wrench or
something and check with a voltmeter to see if it gives a signal.