A Weird Issue...

[trinity]

Hi guys...

I'm facing this crazy issue with my car for a couple of months now which i'm unable to get fixed or rather i'd say unable to locate whats causing the problem. Greatly appreciate if you could share your ideas and experiences in this regard.

Car - Mitsubishi Lancer CS1A

Engine - 1.3L Carburetor (4G13)

Clock - 94K

The issue

Two things happen symultaniously.

1. A whistling kind of noise comes from A/C time to time. No this is not due to an closed ventilation duct. I know the noise comes from the A/C cause when i switch it off, the said noise ceases.

2. When number 1 starts to happen, All lights (Headlights, Meter cluster & Dash board) and radio goes off when in idle. But engine doesn't stall. RPM drop down to about 200. Then if i rev it a bit all comes back to normal but said whistling sound increases according to the rev level.

Why cant it be identified

Issue comes out of nowhere and goes off within couple of minutes, hours or after ending a journey. Or sometimes if i run over few potholes then also it goes away. Means when the car shakes a little its back to normal but not always. So when i take her to the mechanic, she is all good. Issue cannot be recreated at my own will...

When it occurs

First this came to notice when i was driving to Kandy about four months back. It was in day time so i only heard the whistling sound. It lasted about ten minutes and then became normal.

Then on the return journey it kicked back in the night. Lasted about half an hour and got ok when the car ran over a pot hole. Following day i took the car to the mechanic and left it with him. Then i took her back after two days and mechanic said that he only tightened some loose ends but other than that could not find anything wrong with the car.

Then for about a month car was running fine until this good fine evening it started to kick back in the rush hour in Dehiwala. When the car stops at traffic lights & radio goes off and starts to wobble. Then i switched off the A/C and drove home without any problem.

Then on the following day car was fine. Ran about another month without any problem. Then again occurred two weeks back.

To whom did i show the car

Twice to my Usual mechanic. Then at his instructions to an A/C workshop. Since he could not find anything wrong, i went to the place who serviced my A/C about an year ago. He also said he could not find anything wrong by looking at it but asked me to come back when and if the sound comes back again (Like that would happen when i wanted it to happen..).

Finally to an electrician, he checked the alternator current and battery charging and said every thing is on the dot to the standards.

Useful tips

1.Battery is new and both terminals are tighten well.

2.Last year, changed the A/C compressor razor and the compressor clutch (Due to a burnt coil.)

3.There are two belts running on the side of the engine (Pardon me for the ignorance guys, i really don't know what exactly are they called) i believe its fan belts??? changed one belt about one & half years back and the other is i believe has ran about 50k kms.

4.Regular services are done on the dot from the date i owned the car

5.Full A/C service done about one & half years back

Other Indications

Issue mostly occurs at night. But it occurred two times during the day also. (Radio went off and Whistling sound came)

Under normal circumstances, Lets say your head lights are on and when your A/C fans starts to kick in, Lights get dimmed a little. (This is when the car is on idle)

So friends, What do you think is wrong with her??

Many thanks for your support

Edited July 29, 2012 by trinity

[razordj]

1. Not an engine expert but I suspect the fan belts and fans itself.

Stop the engine and turn on the blower with A/C button on and see if you can hear it. If you can only listen to it time to time, may be thats when the A/C starts to work.

2 Battery/ Alternator?

p.s. read through the whole post, but still I suspect those

Edited July 30, 2012 by razordj

[Ripper]

are your fan belt in good shape? inspect them to see if the tension is proper and the belt itself is not damaged. Check for play in pulleys as well while you're at it.

this should be your starting point imho!

[harshansenadhir]

ripper is spot on I guess. I also thought it's the same.

Whizzing noice is the sound at expansion valve as compressor starts. If it reduces within few seconds, alls well. If it continues, check the level of refregirant in the system.

Why lights gets dim is either

1. the load on the system demands more power (A/C clutch coil and auxiliary fans starting) from alternator/battery and it fails to delivery. Bad battery/terminal

-or-

2. loosen or worn out auxiliary belt (no longer fan belt in modern cars

also it's evident that idle speed up mechanism which triggers with A/C does not work properly, that's why RPM drops to 200 (are you sure?). In that sort of a low RPM its natural that alternator cannot compensate the electric demand in the whole system.

[The Don]

I wonder if the compressor is the cause of the issue. A bearing or the rotor inside the compressor might be seizing up temporally putting extra pressure on the engine. This is just a theory of course. The only way to check this out is to inspect the compressor after letting all the gas out. Is your car due for its annual AC service soon?

Also is the AC running well?

[Davy]

Machang, This whistling sound... when you said that it comes from the AC, did you mean you could hear it from inside the car or from the AC compressor (engine bay)?

I experienced a whistling sound from my car stereo some time ago, the sound increased parallel to the rpm, and at night, the brightness of all the lights go dim/bright according to the RPM. The culprit was the rectifier circuit in the alternator. In my case also my electrician told me that everything was fine, but I insisted that he remove and check the alternator. It was only after the alternator was removed the burnt rectifier was located.

Another thing that I can point you towards is the AC fan control unit. The CS comes with an AC fan controller unit that has 2 fan connectors. It's near the fan that is closest to the battery (black box with a heat sink facing towards the front of the car) I have a feeling that one or both the fans or the control unit itself is at fault here. If the whistling sound comes from the engine bay, it could be from one of these fan motors. The control unit controls the speed of the fans as well (dual speed) and in ordinary situations the fans turn on the lower speed whereas if the engine gets a little warm (like when going uphill to Kandy), the control unit sets the fan to turn in a much higher speed (causing a whistle maybe?). My 2 cents.

Please follow up on what others have said as well. Focus on the small things first (like the drive belts for example) and let's see if we can isolate the issue.

[trinity]

are your fan belt in good shape? inspect them to see if the tension is proper and the belt itself is not damaged. Check for play in pulleys as well while you're at it.

this should be your starting point imho!

Hi Machan..

Is there any specific time which you have change the belts? About one and half years back skidding sound came from the belts and i changed a one. In fact that decision was made by mechanics at "Edirisinghe Motors" Matara and they themselves made the change. The person who checked the car said only one belt is faulty, thats why only one belt was changed.

So the remaining belt has ran over 50k kms as i mentioned earlier and frankly speaking machan, i really dont have the proper knowledge to check it myself. I'll be sure to check the belts this weekend as i'm unable to visit any mechanic due to my office schedule..

Thank you for your advice.

[trinity]

ripper is spot on I guess. I also thought it's the same.

Whizzing noice is the sound at expansion valve as compressor starts. If it reduces within few seconds, alls well. If it continues, check the level of refregirant in the system.

Why lights gets dim is either

1. the load on the system demands more power (A/C clutch coil and auxiliary fans starting) from alternator/battery and it fails to delivery. Bad battery/terminal

-or-

2. loosen or worn out auxiliary belt (no longer fan belt in modern cars

also it's evident that idle speed up mechanism which triggers with A/C does not work properly, that's why RPM drops to 200 (are you sure?). In that sort of a low RPM its natural that alternator cannot compensate the electric demand in the whole system.

Thanks Harshan..

Yes RPM drops to about 200 and me pressing the Accelerator only bring her back to life.. But my question is, why is this happening in very long intervals like once a month??

Anyway i'll check the status of the belts in the weekend and update you guys..

[trinity]

I wonder if the compressor is the cause of the issue. A bearing or the rotor inside the compressor might be seizing up temporally putting extra pressure on the engine. This is just a theory of course. The only way to check this out is to inspect the compressor after letting all the gas out. Is your car due for its annual AC service soon?

Also is the AC running well?

Hi machan..

Thank you for the input. Last service was done about one and a half yeas ago. But around October last year, i had to change the compressor razor and the clutch. The place that did the repair said that it'll be just a temporary solution and eventually i'll have to put a new compressor. So i also have my money on that, but Air conditioning is running very well and cant find any fault.

So i'll start with the belts as Ripper & Harshan suggested..

[trinity]

Machang, This whistling sound... when you said that it comes from the AC, did you mean you could hear it from inside the car or from the AC compressor (engine bay)?

I experienced a whistling sound from my car stereo some time ago, the sound increased parallel to the rpm, and at night, the brightness of all the lights go dim/bright according to the RPM. The culprit was the rectifier circuit in the alternator. In my case also my electrician told me that everything was fine, but I insisted that he remove and check the alternator. It was only after the alternator was removed the burnt rectifier was located.

Another thing that I can point you towards is the AC fan control unit. The CS comes with an AC fan controller unit that has 2 fan connectors. It's near the fan that is closest to the battery (black box with a heat sink facing towards the front of the car) I have a feeling that one or both the fans or the control unit itself is at fault here. If the whistling sound comes from the engine bay, it could be from one of these fan motors. The control unit controls the speed of the fans as well (dual speed) and in ordinary situations the fans turn on the lower speed whereas if the engine gets a little warm (like when going uphill to Kandy), the control unit sets the fan to turn in a much higher speed (causing a whistle maybe?). My 2 cents.

Please follow up on what others have said as well. Focus on the small things first (like the drive belts for example) and let's see if we can isolate the issue.

Hi Davy

Sound only could hear from inside machan.. Maybe because when you open up the hood sound of the engine overwhelms the whistling sound. Im sure its not from the Sterio... Let say the sound comes from fans and it only starts when the engine is engine gets warmer, but how come it goes away when you ran over few pot holes??

Anyway you have a point here machan i'll focus on the small stuff first and keep you guys posted...

Thank you for the help.

P.S.

Since you know so much about the CS models i feel like showing the car to you machan,,, Who knows, maybe you could be the man...

[H.C]

As harshan mentioned ,check the idle up unit. I had the similar issue with ac, where randomly idle up mechanism defaulting and found to be oxide in the connector and few puffs of contact cleaner solved the problem. Regarding random power on off situation in the radio feels like some lose connection. Make sure your battery is properly fixed to the battery tray and check wheather that you're using correct size battery terminals.

Edited July 30, 2012 by H.C

[trinity]

As harshan mentioned ,check the idle up unit. I had the similar issue with ac, where randomly idle up mechanism defaulting and found to be oxide in the connector and few puffs of contact cleaner solved the problem. Regarding random power on off situation in the radio feels like some lose connection. Make sure your battery is properly fixed to the battery tray and check wheather that you're using correct size battery terminals.

Hi H.C

I'll be sure to check that when i visit the mech this weekend. regarding battery terminals, yes checked them & they are properly tightened. Terminal size is also correct machan...

Thank you for the support machan..

[Davy]

Hi Davy

Sound only could hear from inside machan.. Maybe because when you open up the hood sound of the engine overwhelms the whistling sound. Im sure its not from the Sterio... Let say the sound comes from fans and it only starts when the engine is engine gets warmer, but how come it goes away when you ran over few pot holes??

Anyway you have a point here machan i'll focus on the small stuff first and keep you guys posted...

Thank you for the help.

Well it could be a lose connection or even a faulty relay that only triggers when a little nudge is given. Again this whole fan control unit is just an assumption, and I just remembered that you changed this entire unit a few months back (right?), so you might want to pay some attention to this as well.

When the whole weird thing happens, stop the car and while the engine is still running, pop the hood and check to see if you can locate the source.

When you replace the drive belts, make sure you give a spin to the alternator and compressor to see if the bearings are worn out/creating additional friction like The Don said. That's a very valid point.

Since you know so much about the CS models i feel like showing the car to you machan,,, Who knows, maybe you could be the man...

lol I’m touched! Things get a lot easy when a friend’s got the same kind of car, remember how you helped me with the AC regulators and radiator?

[trinity]

Hola Friends...

Update....

Changed the belts yesterday.. One belt was in a pretty bad shape and the other didn't look so bad.. I'll let the pictures speak for themselves...

Here you go...

Before removing.

Well here how they look like after being removed..

So friends,.. now its the wait & see time.. dove only about 80kms after the change. So far no issue.. Fingers crossed...

Will keep you guys posted..

Edited August 5, 2012 by trinity

[Davy]

Both the belts seem to be in pretty bad shape, especially the AC belt. I think you did the right thing when you changed the belts regardless of whether they are connected to this issue or not.

Waiting for an update...

[trinity]

Both the belts seem to be in pretty bad shape, especially the AC belt. I think you did the right thing when you changed the belts regardless of whether they are connected to this issue or not.

Waiting for an update...

Machan it happened today... now what... my gut says to check the A/C Unit.. any thoughts??

[Davy]

Machan it happened today... now what... my gut says to check the A/C Unit.. any thoughts??

Did you check whether the alternator or AC compressor bearings are fine (at the belt change)? Also, were you able to pop the hood and try to locate the source of the sound while it was happening?

[whatever]

I had a similar issue, though the noise was different and no drop in RPM. The culprit was AC compressor. Probably the dropping of RPM may indicate the overload caused by defective bearings in compressor.

Edited August 7, 2012 by whatever

[trinity]

Did you check whether the alternator or AC compressor bearings are fine (at the belt change)? Also, were you able to pop the hood and try to locate the source of the sound while it was happening?

I had a similar issue, though the noise was different and no drop in RPM. The culprit was AC compressor. Probably the dropping of RPM may indicate the overload caused by defective bearings in compressor.

Hi Davy...

Sorry for the late reply, Could not check the alternator but A/C compressor baring should be fine as it was replaced last year (I hope we are talking about the same one here).

And no machan i could not check the sound as it was raining outside and i was already late for an errand..

@Whatever

Hi machan... I too now suspect the A/C compressor as this issue only comes when the A/C is on.. And also the compressor had a repair last year..

Ah almost forgot to tell,,, new Symptom... now the Air conditioning of the car is pretty much lower than it used to be and sometimes A/C blows out like mist. And under the hood, there is no water build up on the A/C hose, which usually not like that...

Is my compressor failing???? are all these happening because of that???

Edited August 9, 2012 by trinity

[kushan]

Hi Davy...

Sorry for the late reply, Could not check the alternator but A/C compressor baring should be fine as it was replaced last year (I hope we are talking about the same one here).

And no machan i could not check the sound as it was raining outside and i was already late for an errand..

@Whatever

Hi machan... I too now suspect the A/C compressor as this issue only comes when the A/C is on.. And also the compressor had a repair last year..

Ah almost forgot to tell,,, new Symptom... now the Air conditioning of the car is pretty much lower than it used to be and sometimes A/C blows out like mist. And under the hood, there is no water build up on the A/C hose, which usually not like that...

Is my compressor failing???? are all these happening because of that???

When thinking about the mist ,A/C is low, and A/C hose is not cool enough under the hood, I feels like you have a A/C gas leak.

Take it to an A/C repair center and check where the leak is.

Edited August 9, 2012 by kushan

[terrabytetango]

The mist coming out of the vents is commonly caused by excessive moisture in the blown air, which condenses since the temp is below what they call the dew point (same phenomenon causes condensation on your beer mug). One cause might be the major humidity we've been seeing the past few days, but a more plausible explanation would be that your a/c's water drainage system is clogged up, which means there's no way for the moisture which has been separated from the blown air to escape. Get it looked at ASAP, and get your compressor looked as well. I believe all your woes center around it.

[trinity]

The mist coming out of the vents is commonly caused by excessive moisture in the blown air, which condenses since the temp is below what they call the dew point (same phenomenon causes condensation on your beer mug). One cause might be the major humidity we've been seeing the past few days, but a more plausible explanation would be that your a/c's water drainage system is clogged up, which means there's no way for the moisture which has been separated from the blown air to escape. Get it looked at ASAP, and get your compressor looked as well. I believe all your woes center around it.

Hi Tera..

Thank you for the clear explanation.. Yes now i also believe that this all is caused by the A/C system.. oh man i dont know what to do... Have no money.. Should wait till the Salary day to get this sorted out.. no other option.

[razordj]

The mist coming out of the vents is commonly caused by excessive moisture in the blown air, which condenses since the temp is below what they call the dew point (same phenomenon causes condensation on your beer mug). One cause might be the major humidity we've been seeing the past few days, but a more plausible explanation would be that your a/c's water drainage system is clogged up, which means there's no way for the moisture which has been separated from the blown air to escape. Get it looked at ASAP, and get your compressor looked as well. I believe all your woes center around it.

Let me get this correctly, so you're saying that if the mist comes from A/C vents that is bad?

I get this everyday in the morning when I first turn on the A/C(I'm pretty sure it's mist) and the A/C works fine and the water is dropping correctly under the hood...

edit: It goes away if I keep it like 1 minute.

Edited August 9, 2012 by razordj

[terrabytetango]

If its continuous its bad. If it goes away then its fine. The drier in your a/c probably takes a while to kick in.

Edited August 9, 2012 by terrabytetango

[Komisiripala]

Hi Tera..

Thank you for the clear explanation.. Yes now i also believe that this all is caused by the A/C system.. oh man i dont know what to do... Have no money.. Should wait till the Salary day to get this sorted out.. no other option.

You and most of us too machan! Guess you have to run without AC for a month...

Let us know if that fixes it.