Odd Starting Noise

I have been noticing some weird noises when starting my car. I hear what sounds like a turn signal but they aren't on. Also I hear what sounds like a phone a vibrate coming from underneath the floor boards on the passenger side near the shifter. Any ideas on to what could be causing those sounds? Thanks.

Sounds like your ELC compressor, it's normal for it to run for a few seconds after key-on, but it should be faint in the background. Maybe it's come loose?

Could you please clarify... Are these noises occurring at key-on, while cranking, or after the engine starts?

could be a couple of different thing. we really need more details to be able to help.
here are a few ideas to start the ball rolling though;
the a/c blender doors have a hum to them when stuck.
the ELC makes a racket when filling the rear.
the fuel pump has a buzz to it.
a faulty relay could make noise.

Fuel pumps can be noisy toward the end of their life, so I'm told. Mine is very quiet. The ELC pump is louder. Has it always made the noise, or is it more frequent than it used to be?

I've had the turn signal noise before, but only on occasion, and it usually only happens once or twice. I have no idea the cause, but suspect LCM (lighting control module).

Turn signal sound when signal not on - might just be a weak flasher. If the flasher works funny when it's *on* then replace it and the sound shoud go away (mine did).

(joke follows) as for that phone vibration, might want to recline the passenger seat all the way and find the pocket phone that got stuck there last time you and whats her name were in that seat together, before the battery dies (end joke),

Actually, for that vibration just get a flashlight and look under the passenger seat, also in the console and the pocket in the passenger door for loose stuff.

Oh!! by the way in that vicinity under the car is the heat shield over the end of the cable for the rear oxygen sensor, maybe yours is loose for some reason, It's easy to check if you run the car up on a set of ramps and crawl under. Can't miss it, it's right by the exhaust pipe. While you are under there check the heat shield that's between the catalytic converter and the body pan, maybe it's come loose for some reason.

In your case I strongly suspect one of those heat shields under the car has one fastener missing or some such, maybe due to rust or impact.

Albertj

I once had a buzzing heat shield under the car (where the cat converter goes). Its fasteners were still intact, but it was loose. My solution was to apply a little force to bend the shield slightly, so as to apply some tension. Noise went away and has never returned.

AA wrote:

I once had a buzzing heat shield under the car (where the cat converter goes). Its fasteners were still intact, but it was loose. My solution was to apply a little force to bend the shield slightly, so as to apply some tension. Noise went away and has never returned.

I had the same thought, that's why I want to know exactly when these noises happen. I imagine the 'turn signal noise' is a relay, but is it coming from under the dash or under the back seat...

It happens after I start the car. I have also noticed the buzzing sound while sitting idle after running the car for 10 minutes or so. As for the turn signal sound I have noticed more carefully that when sitting at a stop light it tends to go a lot slower and once I accelerate it speeds back up to where it should be.

The buzz definitely sounds like either the Level Ride pump or the loose exhaust part... I'd suggest starting the car and lying down on the ground with your head below the passenger door jam, to see which direction it's coming from.

Speaking of direction, you still haven't said which way the turn-signal noise is coming from...

crosss3 wrote:

It happens after I start the car. I have also noticed the buzzing sound while sitting idle after running the car for 10 minutes or so. As for the turn signal sound I have noticed more carefully that when sitting at a stop light it tends to go a lot slower and once I accelerate it speeds back up to where it should be.

Buzzing sound: If it just buzzes a little then quits, it is the pump for the air suspension. If it does the same sort of dull buzz frequently then you probably have a leaky rear shock, replace both of them it's not that much or that hard to do. Telltale is if it runs I think 30 seconds then quits, then again 5-10 minutes later with no change in the way the car is loaded (passengers, luggage, gas) then you have a leaky shock. The air ride should not run all that much.

Other than that - please don't take this personally but will you please go check the heat shields already. No matter how many times you ask about this, you won't eliminate that (or any other) possiblility unless and until you go look. What to do: when the car is cool (before you've used it that day or a couple hours after you have driven it) either jack it up and support it on jackstands or drive it onto a pair of ramps (autozone, about $30). Just behind the front wheels, under the centerline of the car, above the exhaust you will find one (big) heat shield and next to the exhaust a foot or so back you will find another (actually more of a splash shield) over the wire to the rear oxygen sensor. Try to shake the shields with your hands. If they move at all, you've likely found the problem.

The other thing you can do is start the car while it is sitting on the stands/ramps. Be sure to chock wheels/set parking brake. Under the car you will be able to see the air ride's air compressor just in front of the rear wheels and up against the body pan. Let the car idle a few minutes. After a while (I forget, it is 5 or 10 minutes or some such) the pump will come on, and you'll be able to confirm that that's the source fo the sound. Be sure not to touch the exhaust while under the car, it gets hot from the catalytic converter and fumes.

Another source of the buzz might be worn motor or transmission mounts. most likely culprit would be the rear transmission mount. It is bolted to the transmission case and the rear of the car. With the car up on ramps or jackstands it's easy to spot, It has a rubber insert in it. If the rubber is twisted or checked, it's not going to be stiff enough to damp vibrations enough and you will get a rumble or buzz.

Based on what you say about the turn signal sound, I still suspect a weak flasher. Any car parts store has replacements, either 'thermal' or 'electronic.' If you have never replaced it, they are not really worth testing -- just get a replacement and be done with it. You can 'cheap out' by scavenging an electronic flasher from a car in a junkyard. If it's not the flasher, it might be time to replace your battery - a weak battery in these cars causes *all kinds* of weird problems because the load on the battery when the car is off is actually very high. In case you were wondering, battery is under the rear seat. Have it tested at a Sears or other auto service center to determine if it has enough "cold cranking amp" capacity (CCAs, not just CAs). Push in on the leading edge of the seat while lifting up and the seat will come out. It is on the passenger side, easy to spot. While you are under there make sure the vent is hooked up and the floor has not rotted from acid fumes - if so, I'd say that is your 'fix it now' problem and the buzzing and clicking can wait. Anyway - reverse the seat maneuver for reinstallation. As for the battery, be sure to get the same type (Group 79) battery with a replacement vent if it's a different size--if you don't the fumes will cause problems pretty quiclkly. You may find that your nearby discount store (walmart, autozone) has such batteries. And there is an "Interstate Battery" dealer in just about every county in the USA - battery may be cheapest there, expect to spend about $130.00 or so not including the new vent of you need it. Search this forum for the part numbers.

I have to go. Point of all this is that as far as I can see you've been told what you can be told about the likely source of the problems and you now are going either to roll up sleeves and fix it or take it somewhere. Good luck.

Albertj

Albert
Thanks for the reply and sorry for taking so long to get back with you as I was out of town for work. As far as the heat shield goes I checked that and everything looks fine. I dont see any problems with the heat shield being loose or anything of that nature. I am going to replace the rear shocks and see if that helps at all. Even if that is not the cause of the buzzing it needs to be done anyway. Do you or anyone else have recommendations for rear shocks? As far as the turn signal noise i'm a little confused as to what you mean by a weak flasher. Are you talking about just the bulb or is it something else. Thanks.

crosss3 wrote:

Do you or anyone else have recommendations for rear shocks?

I have a set of brand new OEM Delco shocks in the box if you are interested. PM me.....

crosss3 wrote:

Albert
Thanks for the reply and sorry for taking so long to get back with you as I was out of town for work. As far as the heat shield goes I checked that and everything looks fine. I dont see any problems with the heat shield being loose or anything of that nature. I am going to replace the rear shocks and see if that helps at all. Even if that is not the cause of the buzzing it needs to be done anyway. Do you or anyone else have recommendations for rear shocks? As far as the turn signal noise i'm a little confused as to what you mean by a weak flasher. Are you talking about just the bulb or is it something else. Thanks.

No the flasher. It is a little metal can shat should be in a clip on the aluminum frame that holds the steering column. you have to pull the panel from under the steering column and hunt around for it. There are 2 - one for turn signals and one for 4-ways. When you ahve the panel off, turn on the 4 way flashers. The little can that is clicking is the 4-way flasher, and the other one that *looks* the same is the turn signals. Previous owner may have installed an electronic flasher in which case they can will look a little different,

Albertj

If someone hasn't reversed them, the turn signal flasher is the one on the left... But didn't you say the clicking noise is when the turn signal ISN"T on?

Eldo wrote:

If someone hasn't reversed them, the turn signal flasher is the one on the left... But didn't you say the clicking noise is when the turn signal ISN"T on?

When my flasher got weak I noticed it'd sound off (click) once in a while. I simply replaced it. Put in one I pulled from the pick and pull. After about a year, did it again, So I bought an electronic one at autozone, I think it was $12.00 End of problem.

Why it does this I am not sure, I wonder if a look at the schematic will reveal something... what I would be looking for is something that would ground the flasher circuit ahead of grounding the lights (so the lights do not flash) or a source of voltage spikes on the supply side.

Albertj