97 Protege Engine light and odd chirping noise.

[Trooper]

I currently own a 1997 Mazda Protege SE, 4 door.

It has a lot of milage on it (192,000km's)

It still runs well, but there has been an ongoing issue with the engine light. It would come on when I turn the car on, and a week later it would go off. Then a week later it would come on again.

This has been going on for about 2 months now. I took it into Canadian Tire and they told me it was due to a loose gas plug or something (im not too car savvy...) but it still happens. They can't find anything else wrong with it.

Also, the engine makes a strange chirping sound when its running. It gets louder when I turn on my rear defroster.

At first I thought it could be a heater issue, so I turned it off to see if the noise would go away, but it didnt.

it's coming from the right side of the engine (or when you are looking under the hood, its the left side)

Any ideas what this could be cause by?


Thanks in advance!

[MazKid]

I currently own a 1997 Mazda Protege SE, 4 door.

It has a lot of milage on it (192,000km's)

It still runs well, but there has been an ongoing issue with the engine light. It would come on when I turn the car on, and a week later it would go off. Then a week later it would come on again.

This has been going on for about 2 months now. I took it into Canadian Tire and they told me it was due to a loose gas plug or something (im not too car savvy...) but it still happens. They can't find anything else wrong with it.

Also, the engine makes a strange chirping sound when its running. It gets louder when I turn on my rear defroster.

At first I thought it could be a heater issue, so I turned it off to see if the noise would go away, but it didnt.

it's coming from the right side of the engine (or when you are looking under the hood, its the left side)

Any ideas what this could be cause by?


Thanks in advance!

Gas plug? Looks like Canadian Tire has BSed you. While the check engine light CAN come on from the gas cap being loose, surely you've filled the car with gas more than once in those 2 months and the likelyhood of the cap being loose each time is very low. However, an aftermarket gas cap might not work as a stock Mazda cap and can cause the check engine light due to low fuel tank pressure. Again, it's not likely.

I'd suggest taking the car to an authorized Mazda dealership to have the CEL code read and properly diagnosed.

The chirping sound comes from the alternator. When you turn the defroster, or any "accessory" on, it draws more current which makes the alternator work harder. The chirp should be relative to engine RPM, in that when you rev the engine the chirping should speed up too. You haven't mentioned any loss of electrical power that would normally be seen with a bad alternator(if it does happen, your radio will turn off, dash lights will flash, tachometer(ohh, doh, you have a SE = no tachometer) will surge up and down, and your headlights will dim. If it gets bad enough your battery will drain and your car can shut off at idle because it doesn't have spark anymore), so I don't think the alternator is bad. Could be a simple thing like an irregularity in the belt and/or pulley that creates a chirp at a certain part of the rotation of the belt. It can also be in the alternator itself. If it bothers you enough you can have a Mazda mechanic check it at the same time you get the check engine light read, they'll usually be able to tell you what the sound is right away.

[Trooper]

I think you may be right when you say the belt. I was looking under the hood yesterday and the chirping noise seems to be coming from the belt area.

But then again, what would cause the chirping noise to become louder when I turn on my rear defroster?

Is this something serious that should be checked out right away, or can it wait? I'm a bit short on funds to foot the bill to have anything repaired (went to town on christmas gifts this year :p )

[MazKid]

It gets louder when you turn the defroster on because it's making the alternator work harder to keep current in the battery. When the alternator has to work harder, the force needed to turn the alternator increases, thus the noise gets louder. Usually when you turn the defroster on, the car's idle will bump up to compensate.

I'd say without any other problem other than a noise, you can wait on it.

[1st Gen]

It gets louder when you turn the defroster on because it's making the alternator work harder to keep current in the battery. When the alternator has to work harder, the force needed to turn the alternator increases, thus the noise gets louder. Usually when you turn the defroster on, the car's idle will bump up to compensate.

I'd say without any other problem other than a noise, you can wait on it.

Yeah, what he said.

One thing though. The chirping should happen when you turn the lights on too as I'm pretty sure they draw more power that the defrost motor. It could just be a loose belt.