GS400Star

Symptoms
1. Rough Idle
2. Loud high pitched noise coming from engine - sounds like metal on metal but I dont think it is. Maybe bad bearing sound?
3. Engine noise is there at idle and low revs but goes away as I rev the engine
4. No loss of power
5. No CEL

I looked under the hood and the noise seems to be coming from the water pump area but I cant be sure. Could a water pump make this noise if it was about to fail?

The car has 193,000 miles and the timing belt and water pump were changed at ~ 98,000 so it seems likely that the water pump would be due for replacement soon and even if it wasn't it might as well be replaced if I'm going to change the timing belt.

I made a video of the engine noise if you would liek to hear exactly what it sounds like.

Thank in advance for any help you can provide.


http://youtu.be/GB8f3g3j-c8

TWong350

iTrader: (8)

Wow...that sounds terrible. Where's the sound coming from? Rather, what part of the engine bay is it coming from? Front of the engine could mean it's the water pump. But, it could be a number of other things too. I take it you've checked out level and whatnot?

GS4_Fiend

iTrader: (22)

Smart of you making the video. Is the oil level good? What's the condition of the oil? Buy a decent vacuum gauge and get it hooked up any where on the intake manifold and see what the vacuum reading is. The reading should be a steady 18-21" of Hg. Then report back.

clos430

iTrader: (21)

Sounds like a bad pulley, tensioner/ water pump. Remove drive belt and start engine to see if noise continues. If so most likely it's coming from the water pump. Almost 100k miles on it so i think it's time to replace it.

DeanGS

iTrader: (8)

Yeah, pull the belt off and see if the noise is still there. It sounds like about 4 taps per second which equates more to a valve train issue (if idle is around 600 rpm or so). Might be a collapsed valve spring (piston hitting a partially open valve) but I've never seen that on a 1U/3U.

Rock-a-Lex

iTrader: (4)

Agreed. But if its not the belt I would def check the engine oil level and its consistency. The 1uz does funny things when the oil level is too low or too high, good luck!

Bippu147

iTrader: (9)

check the crank damper

cdg306

Start with your tensioner. They make horrible noise when they start to go. Could also be water pump. Do you have a length of pipe like a jack handle or something? Put it up to your ear and it will help you isolate the noise to a particular item.

GS400Star

Thanks for the suggestions. This Saturday I will try and locate the issue from the suggestions here. Will check the oil too.

Thanks

FrankT

Remove the serpentine belt and run the car a few seconds.

My guess is the ac compressor has a stuck valve.

Good luck and please keep us posted.

GS400Star

I assume you don't mean the timing belt. IS there a DIY write up for removing the serpentine belt?

GS400Star

Its rod knock. Car is officially dead.

ThomasGS4

iTrader: (19)

That burns.


Any plans for a new engine?

Bippu147

iTrader: (9)

or part out?

lol

GS400Star

checking with a mechanic on the cost of a used engine or the repair of the current one. What I do will depend on the cost. It was a great car until now.