I hope someone can help me pinpoint my problem & what I need to do to fix it . I have a 1994 Honda Accord EX.


For a while now it's been making a weird noise whenever I start it up and randomly when its running (both in idle & while moving). I think it's the air compressor, but i'm not sure. I have A/C & heat, but I don't have to be running them to get the noise. Whenever the noise kicks in my RPM's drop 100-200 rpms then come back up when it stops. In the summer only a few seconds, but in the winter at start up it'll last a good 10-15 seconds. When I turn my A/C on my RPM's drop to 100rpms for a few second then comes back up.

I took a video of the engine & noise to explain it better, because I know I can't.

1994 Honda Accord 'Rrrrrrrrr' sound (possible air compressor issue) - YouTube

(please excuse the crappy narration & the dirty engine)

I have not had it looked at professionally yet. My check engine light never kicks on. All my fluids are fine.

 

Its still kind of tough to locate the noise. Does this happen every time you start up the car and let it idle?

 

This is one of those situations where a mechanic's stethoscope can help isolate the area easier when that sound occurs. Just have to be careful of where your hand and body is due to the moving parts when listening with the scope.

A mechanic's stethoscope is usually around $15 -$20 at most auto part places and Sears.

 

Yes, the sound happens everytime I start it and often when i'm driving. It does it for longer periods in the winter.

 

Thanks for the advice, I'll see if I can run to one of the stores and pick one up today and post what I figure out!

 

My two comments.

One, the first line below the 1K on the tach is 750 rpms, the second is 500 rpms and the bottom.....well is zero.....so about 1:49 in the video the car is at 750 rpm's,,,,,,normal

Second, put your hand on the abs pump....when the noise happens....can you feel it on the abs pump?


PS- I'm glad it wasn't a sick rooster and I didn't wake anyone up while watching.....a joke on me on here, some will get it......nothing to do with your issue. Just a joke with friends here. Sorry for that.

 

certainly needs a valve adjustment regardless...

 

First off, I didn't know that about the RPM's so thank you for telling me. Right at 1:49 the RPM's are normal, it was right before that that they dropped down really low.

Second, your a genius! The sound is coming from the ABS pump (I felt it and also confirmed it with a stethoscope to just to be sure). I would assume that the pump isn't suppose to make that sound and needs to be replaced?

When I got the car they said the ABS senor was bad and that caused the ABS light to come on and off (thinking about it now, i feel really stupid that I believed them since when the light comes on it means the ABS isn't working at all).

Also, since its not the air compressor making the noise, what is causing the RPM's to drop so low when the A/C is running?

Your right about the joke, no idea what you mean, but thats ok!

 

Trust me the car needs a lot of things, but its better than when I got it. I'll add that to the list too though!

 

Again, I get lucky every now and then....but I still have one of these so some of the sounds....well I get to hear them every now and then.

I was watching the video trying to see the abs light, it never went far enough to the right to tell.

In the Common DIY Threads sticky at the top there is a "how to get codes" for this generation (5th gen): https://www.hondaaccordforum.com/for...threads-40780/

When you "jump" the service connector, you will get code from all of the computers - looked like the srs was on, there is a different procedure for getting those - get the codes from the ecu, tcu or abs by jumping the service connector and let us know what they say.......I'll "guess" again that you get a code one from the abs which is a pump over-run"....but get the codes. We can go from there. It could be as simple as bleeding the abs unit and filling the abs res - different than the brake mast cyl res.

For the idle, in the same link above, read about cleaning the IAC and FITV valves.

If you are not sure when they were last changed, replacing the dist cap, rotor and plugs can't hurt anything. You also set a baseline for when to do the next tune up.

Let us know what you find.........