High pitch humming sound and burnt smell

[Glyuen]

need help.. i just done my servicing yesterday. the only thing done was change engine oil and top up coolant water.

 

today when i start my engine there's this funny sound that does not go away, its a high pitch mmm... sound.. then when i accelerate and change gears it follows.. as in if you had sat TIBs buses.. that wad it sounds like. then when i get out of the car.. the engine bay reeks of burnt rubber/plastic smell but i cant seem to pinpoint where is it coming from.

 

any one has an idea what happened? or any good place for a diagnostic check tomorrow?

[Siyexcalibur]

a)Sounds like you have a loose/slipping belt somewhere in the engine compartment. Check belt tension according to your manual. If loose tighten the belt will do.

 

b)If belt not loose, maybe pour engine oil that time spill some on belt causing belt to slip. You can try belt grip spray or just change the belt if you know which belt.

 

c) Jam pulley/bearing, You are in real trouble, you can see the pulley not turning smoothly.

 

Start diagnosis from (a) to ©, (a) most likely

[Glyuen]

thanks. but how do u check belt tension? i've lost my car manual.

[Bugsbunny]

go back to service center to check again.

play safe.

[Application9999]

don't think he should even driv it to the repair centre..

[Siyexcalibur]

I dont know how many belts you have in your car.

 

To check belt tension

For every belt, you press it and feel the amount of deflection. Your manual will tell you if you use so much force, it will go down by so many mm. There is a range given, if you exceed that it is too loose. For example see below, your car will have different spec, I dont know? I took the following from a car service manual

Edited April 19, 2008 by Siyexcalibur

[Glyuen]

thanks for your suggestions. apparently it is something more serious than that. the problem is a failing alternator. on sun morn i could not start the car. tried to jumpt start also cannot.batt totally flat. called AA roadisde assistance. van came and say my batt needs to be replaced. so bought a $200 batt from them ( i know i kana chop carrot cos i ask outside workshop say at most $160.) can start liao.

 

then today afternoon same thing happen. i very du lan call AA. this time the van took 2 hrs to come. the mech really check everything.. in the end measure charging current and found out that alternator failing. but out of goodwill replace the 1 day old batt for me. since under AA warranty.

 

i drove to workshop to replace alternator. now no more burnt smell or humming sound.

[Octopus]

Good to know you got the problem fix.

 

My colleague's 3 years old Vios a few weeks ago also got some noise from the engine compartment area, one of the workshop diagnose its the air-con compressor problem. But he didn't get that fix cos he'll be getting the new Altis very soon.

But unfortunately, just 2 days before collecting the new Altis and trading in his old Vios, his water pump broke (pulley drop off ) while on his way home. Turns out that the noise was from his water pump all along...

[Siyexcalibur]

200 dollars battery is very very expensive, I think at most $120 outside. What brand AA provides?

[Yeobh]

The 1st van mechanic is really incompetence. Without checking the charging system he jumped to conclusion that the battery is aging or faulty.

 

Try to get hold of a battery/alternator monitoring device so that you can can have the battery and charging status info right infront of you when driving. The small investment will cut down all the downtimes, worries and headaches

[Yeobh]

Without a proper mechanic stethoscope, it almost impossible to detect where the noise(s) coming from - it is like looking for the needle in the haystack.The mech just BS at the car owner's expense if he buys his recomendation to replace the air con compressor.

[Thug]

Must be ur belt...go check asap bro....

[Fcw75]

 

He aleady said it's the alternator leh. Wat belt?

[Glyuen]

i also tot so.. some hopepecker.. supposedly made in germany. i dunno how to spell. haha

[Glyuen]

ya.. i was thinking to ask AA to give me back my old batt. the day before the indicator is green... sigh.. but wad's done is done already. no point.

 

hmm.. where to get such a device? i've never seen one before..

[Siyexcalibur]

There are a lot of such devices around in the DIY/car maintenance section, you can plug it into the cigarette lighter socket. The LEDs will inidicate the alternator condition when the car engine is on and the battery condition when the car is off.

 

You can also use a multimeter if you have one, the voltage should be about 15V when the alternator is running and about 12V when the car engine is off.

[Albeniz]

don't think he should even driv it to the repair centre..

 

Yeah... ask the service center to tow it back, it's their fault!

[Thug]

haa..din read the rest of the thread...