Brad wrote:

> I have a 96 civic EX with 110k on it. It has been a great car, the only
> thing I have ever had to replace was the alternator and battery. I replaced
> the timing belt not too long ago just to get it out of the way.
>
> The engine however many times make a deep knocking when in low gear or going
> up a hill, especially when the engine is cold. The dealer could not find
> anything and suggested moving up an octane. I am curious if I should some
> STP treatment to clean out the engine. I am not very car savy---cant even
> change my own oil---so is the STP stuff safe?
>
> Any other advice to take care of the engine? All my driving is stop and go
> and I get the oil changed every 3k.

If the knocking sound resembles a metallic pinging, I believe I answered
this for somebody else recently. Try a higher quality gasoline brand,
regardless of octane. It worked for my '93 Accord after a few fill-ups.

Of course, has your car been tuned up recently? If the ignition timing is
off, that could also cause the knocking or pinging.