humming noice

voudon

New member
Joined
Jul 23, 2015
Messages
12
Reaction score
0
Points
0
I have a 2000 Sunfire Coupe, 2.2. I just recently bought it and I am working on getting all the bits worked out. The engine runs great etc but I have noticed when I am accelerating there is a hum that gets quieter as I get up to speed and stops when I am at the steady speed. I have also noticed that the gas pedal doesn't have a steady speed pressure spot like most cars I have owned. Last week I had the brakes done and they said a bearing (my ABS light is on and it checked out as working when they drove it) was in the early stages of going out but that they couldn't tell me which because the computer didn't recognize the vehicle.

I am hoping it isn't a transmission issue and just the bearing. I don't get a loss of power or sticky shifts, it is an automatic, no smells, no fluid on the ground. It doesn't jar when it shifts, sometimes you can feel it but very smooth. Not a lot of oomph in take off. Thanks for responding.
 
Wanted to add that the humming only happens when i press the pedal down and stops when I let off the pressure. It also gets quiter the faster I go.
 
Do you hear the noise when in park and you raise the engine speed? I'm puzzled why they couldn't connect to your ABS system to find the problem. They could also have used an ohmmeter to check each of the sensors.
 
Do you hear the noise when in park and you raise the engine speed? I'm puzzled why they couldn't connect to your ABS system to find the problem. They could also have used an ohmmeter to check each of the sensors.

Nope. But in park it is loud, not like gee man what is up with your car loud, but shifting into drive or reverse there is a noticeable change to a quieter sound. It just makes the hum when I give it gas to accelerate and stops at about 35 or 45 or rather gets quieter as I am not sure because of road noise.

I didn't go to a mechanic to get my brakes done, just a brake shop in town. No idea why they didn't use the ohmmeter but i was in a hurry lol
______________________________
 
Well lets add overheating when stuck in traffic. In Louisville there is a lot of construction going on and I hit a five mile patch of 20 mph or less with constant stops. Today is the first day it has done this after driving from my girlfriend's place to work and I am sitting in a parking lot waiting for it to cool down. It got in the red while sitting on a bridge but was able to get off and pull over. So gonna be late.
 
I've hit this patch before with no temp problems. Pulled over and checked the coolant and the oil and they are fine. The lights come on and off all the time even after a change and we thought a bad sensor. Could it be related to the humming?
 
Not that I could tell. My ride got me before it could cool down enough to check. Having it towed to a mechanic tomorrow. I had a car where the head gasket went out so I know how that works and this wasn't like that at all. I had already sat in traffic for about ten to fifteen minutes waiting to get somewhere when it started kicking up, slowly at first. When my old cars head gasket went out, it overheated whether I was moving or stopped. I guess I will know tomorrow for sure. I called a mechanic that luckily hadn't left yet and told him everything and he said cooling fan from the sounds of it but without looking at it he couldn't say how it has gone out which I expected.
______________________________
 
Now that I have the car back, even those pesky coolant and oil sensors aren't coming on. Woot. One problem solved. Now I've tested the hum while the car was in park I revved my engine and yeah it hummed.I am think the belt?
 
You had it at a shop and didn't ask the mechanics opinion?
 
which bearings, the alternator has a bearing, the idler pulley has a bearing, etc. Engine bearings make a knocking noise not a hum.
______________________________
 
which bearings, the alternator has a bearing, the idler pulley has a bearing, etc. Engine bearings make a knocking noise not a hum.

They were closing up and I needed to get to work but they said wheel but as I described more they told me some tests but it isn't the wheel. That's when I thought to do your original suggestion of revving the engine in park so I did when I got home that morning. Still a hum. And the muffler is loose too. Oy. That's an easy fix but the hum, yeah I'm thinking something in the belt like the oil, water or ac compressor. Leaning to AC compressor.
 
Hmm my reply didn't post. Wheel but I already know it needs work and when I did the park test it still hummed so while the front right needs replaced, don't even hear it, know from having gotten brake work done and they were checking the ABS light, and it isn't the transmission either. I'm thinking the belt system, primarily the AC compressor. The AC I rarely ever use in a car anyway as I like driving with the windows down, I turned on yesterday and was weak or intermittent after the dealer had recharged it when I bought it.
 
Well changing the bad fan helped... Sort of. Still gets hot when I idle but not as fast and turning on the heat keeps it steadily at the second hash mark above 195*. Oil light also came on after about 15 minutes when I was idle but driving back in this stupid louisville traffic today it eventually quit coming on. Ugh.
 
Did you check the oil level when cold?
You didnt mention a "bad" fan before?
When cold is the coolant at the correct level?
Try using a length of rubber hose, hold one end near your ear and move the other end around to find the source of the "hum" noise.
______________________________
 
The fan went out Thursday on my way to work. Checked the coolant and oil and they're fine.
 
Back
Top