91 Corolla Knocking Noise

If you are lucky, the knocking noise could be your water pump. In the good old days, you could grab the fan and 'tweak' it from side to side; if it moved, it was the water pump. You *could* try to do the same with the pulley and see if it wiggles.

Yeah, but I definately think its coming from the crankcase. Of course I could be wrong. Any way to be sure?

Like I said, see if you can grab the pulley. If it moves more than 1/4"...

Its hard to tell, but that than noise may be a leak around the exhaust manifold. Perhaps one of those stethascope thingies could be used to locate the source.

Merritt

"" wrote: > I have a 91 Corolla with 145k (4A-FE engine). Lately, I've > been hearing > a faint knocking noise that is definately coming from the > engine. Its > only really noticable when the engine is cold but I listened > closely > and it is also there very faintly even when the engine is > fully warmed > up. I'm afraid this may mean major engine repairs. However, > the car > still seems to drive normally. Any ideas? > > Also, unrelated to this I've been noticing that the car has > been > getting louder and louder over the past year. Even before the > knocking > started (or before I noticed it). I just got the muffler and > tailpipe > replaced (muffler was falling off) and the car is still much > louder > than I remember it being. Could it have something to do with > the > exhaust manifold? Its probably unrelated to the above knocking > issue, > correct? > > Thanks, > Jacob

If the knock gets quieter when it warms up, it maybe be piston slap from wear. If it get louder as it warms up, it is usually a rod bearing. Piston slap is not fatal but it will get worse with time and will be the worst on really cold morning until the piston warms up and swells in the bore some.