Ugly splat/knocking noise

[sc0rpi0n]

I have searched the forum for a problem like mine, but i dont think i can fully relate to anyone elses. I have a BA v6 2.5 (kl-ze) that is right now making some louder then usual unhealthy noises. Kind of hard to explain, but its making a splat like sound every 1 or 2 secs as the engine is turning and in the background there is a constant knocking noise. Im yet to take it to mechanics, but i thought id ask here first to see if its something i can take care of myself.

[bourbon]

where is the noise coming from? engine or wheels, gearbox suspension?

[sc0rpi0n]

engine.

[sc0rpi0n]

the noise seems to be irrelevant of acceleration...its fairly constant

[sc0rpi0n]

any suggestions anyone... does this sound like the bearing is stuffed...or water pump...?

[RedLineResident]

Hydraulic lifters maybe. It is more of a click/tap as opposed to a knock, and does it appear to be coming from under the rocker cover?

[chewyryce]

Just get a long screwdriver or a long metal rod and place it on the parts that you think the noise is coming (preferably not on the moving parts) and put your ear close to the other end of the stick/screwdriver. the sound should travel through and you should be able to listen to the noise.

Possible places to listen:
- Rocker cover like what RedLineResident mentioned.
- Water pump
- Alternator
- A/C
- Tensioner and idler bearings
- Timing cover (just in case the other bearings are gone and you cant actually see them)
- Crank/Sump

NOTE: some noises may not appear unless on load. but if this noise is evident on idle then it should be easy to locate.

Also. does the car run rough? or it hasnt change at all?

[Cosmo Dude]

If the noise doesn't change with revs then I'd check things like power steering, themo fans etc...

[sc0rpi0n]

Actually today i noticed it does change with revs, gets much louder.

Its not the lifters im concerned about, those things make noise anyway(im used to it), esp with lower grade petrol...which is what was the knockin noise in the background is.

What I am concerned about is the other noise that im getting like i said every one or 2 secs like as if something is loose, which seems to be coming either from the tensioner, idler bearings or the under the timing cover. When i am driving and stop at traffic lights, the revs dont sit at the usual 800, but rather go down low to 400-500...

[NaughtyGT]

check your timing buddy. If revs have changes to that low I suspect timing belt/tensioner. Advice, get it looked @ & save yourself the headache & further complications. Even then, you can go home & fix it if it's something simple they find. If not, it's been worth it. Do you know a trustworthy shop? Could be a sensor too? but shop will be able to diagnose quickly

[sc0rpi0n]

yeah thats what i fear, the shop telling me its somethin much worse then just a sensor or loose belt.
does the fact that the longer i drive the louder it gets make any sense. I drive for an hour to work, and in the last few minutes of my trip, the noise is much higher then when i left home... then when i leave from work again not as loud as it gets once home.

[NaughtyGT]

you sure it is the above half of the engine? Not coming from bottom end @ all? What's temp like? Is the noise coming from water pump area? Wonder if it's not big ends? Have you taken it in to shop yet or just spoken over phone?

If it was a broken belt, obviously you wouldn't be going anywhere. What concerns me is the idler/tensioner may have given way? If this is the case, you better get it fixed ASAP before you do damage, if you havn't already? @ the very least you'll have to get belt done as a complete job (belt & assoc' parts). You don't do part the job I'm afraid. It's kinda a noway out maintenance job. Sorry.