strange scary noise coming from my motor, help.

**02ultraZ** · 08-06-2007, 08:20 AM

Ok i have an '02 Z with 30k on it. It does have the piston slap. There is a new noise that has only happened twice but it sounds horrible. Each time i drove my car like 40 miles, then it sat and cooled for like 6 hours or so. It was still like 80 degrees out so it's not like it was that cold. But when i fired it up there was a whine coming from the motor. I know it was the motor. But the first time it did it I thought i was the throw out bearing for the clutch but only because of the initial sound. I was playing with the clutch and it didn't change the sound so i know it wasn't that. The sound sped up so to speak when i gave it gas. I really have no idea what the hell it is, it went away once it warmed up. Help me out guys i don't have a clue. I put 10-30w in the car perhaps the wrong oil if i have the piston slap?

**LETHALxLS1** · 08-06-2007, 10:33 AM

I had a similar noise a long time ago that just went away but may not be what you are experiencing. How bad is the piston slap-on a cold start how long does it take till the slap goes away? I use 10-40 in my car.

**02ultraZ** · 08-06-2007, 10:49 AM

eh, piston slap is pretty loud, i don't have headers and i heard it get louder with headers but i'm not sure. After the car is at norm op. temp. the slap is almost completely gone. Sometimes i don't hear it at all when the car is warm. This noise also changes with the RPM's.

**LETHALxLS1** · 08-06-2007, 11:05 AM

Damn dude I would be pissed if my car had such low miles and slapped even when it got warm. Any chance it could be a lifter or valvetrain related?

**02ultraZ** · 08-06-2007, 12:29 PM

Originally Posted by BREAKxNECKxSPEED

Damn dude I would be pissed if my car had such low miles and slapped even when it got warm. Any chance it could be a lifter or valvetrain related?

You mean the piston slap or the new noise i'm hearing? If anything in the motor is sounds like a bearing whining but i don't know yet. Each time i heard it i was in a rush so i didn't get to check it out that much.

**camarojunky74** · 08-06-2007, 03:20 PM

take your serpentine belt off and run it like that for a few seconds and see if the noise goes away. you may get lucky and find a bad idler pulley or maybe a pump or something let me know

**LETHALxLS1** · 08-06-2007, 04:07 PM

Originally Posted by 02ultraZ

You mean the piston slap or the new noise i'm hearing? If anything in the motor is sounds like a bearing whining but i don't know yet. Each time i heard it i was in a rush so i didn't get to check it out that much.

I was talking about the pistin slap-seems odd that it doesnt go away when the car gets warm. All I can suggest for the whining problem is letting someone you trust as a mechanic listen to it. I do not suggest taking it to GM service-ever. Maybe you could make a video so we can hear it also.
Good luck bud.

**Orcus79** · 08-06-2007, 04:13 PM

Ever think it could be your AIR pump, mine whines like blower till it warms up, I come on if the car has cooled enough to drop below a set range.

**02ultraZ** · 08-07-2007, 07:13 AM

Originally Posted by Orcus79

Ever think it could be your AIR pump, mine whines like blower till it warms up, I come on if the car has cooled enough to drop below a set range.

Thats what it sounds like a blower, i think you guys are right about the air pump, i fired the car up and took it for a spin last night. It didn't make the noise. It sat for an hour and i started it again and still nothing. So if it's my air pump would it be so inconsistent?

Thanks for all the help guys

**camarojunky74** · 08-07-2007, 07:44 AM

because all it does is suck fumes from the gas tank, it doesnt always need to do it, its based on engine temperature, and fuel range. i think. but yeah it kinda sounds like a little vacuuum, its located under the relays and fueses on driver side close to the front of the car,

**Raven02ta** · 08-08-2007, 12:38 PM

Originally Posted by camarojunky74

because all it does is suck fumes from the gas tank, it doesnt always need to do it, its based on engine temperature, and fuel range. i think. but yeah it kinda sounds like a little vacuuum, its located under the relays and fueses on driver side close to the front of the car,

ok, the air pump does not suck fumes from the gas tank (there are no lines running from the pump to your fuel at all). the AIR pump, upon cold starts turns on an electric motor and pumps air from the side of your airbox after the air filter (the tube going into the side of the airlid) to the motor and then pumps that air into the tops of BOTH of your exhaust manifolds directly (Via, A.I.R. Tubes) this is done so that when when vehicles are on rollers for emissions the air pump forces the clean air in to the exhaust so it seems that the vehicle burns cleaner.

**camarojunky74** · 08-08-2007, 12:51 PM

oh snap my bad, i was thinking of the damn charcoal canister for some dumb reason..

yeah your right... nice

**02ultraZ** · 08-09-2007, 06:25 AM

Originally Posted by Raven02ta

ok, the air pump does not suck fumes from the gas tank (there are no lines running from the pump to your fuel at all). the AIR pump, upon cold starts turns on an electric motor and pumps air from the side of your airbox after the air filter (the tube going into the side of the airlid) to the motor and then pumps that air into the tops of BOTH of your exhaust manifolds directly (Via, A.I.R. Tubes) this is done so that when when vehicles are on rollers for emissions the air pump forces the clean air in to the exhaust so it seems that the vehicle burns cleaner.

So do you still think this would be making this noise? And then what shuts the air pump off when the vehicle is warm. And also when it does shut off does it slow down then shut off, or shut off completely instantly. The reason i ask that is if i listen to the car when i hear this whine and the whine slowly goes away, or the whine stops instantly, i will know it's the air pump. And i still haven't heard it again. So it's pissing me off.

**Raven02ta** · 08-09-2007, 06:32 AM

Its actuated by a relay which i think is kicked over by the coolant temp reading in the pcm. the pump winds down when it turns off.

**02ultraZ** · 08-09-2007, 10:01 AM

Originally Posted by Raven02ta

Its actuated by a relay which i think is kicked over by the coolant temp reading in the pcm. the pump winds down when it turns off.

So it winds down only taking a few seconds, meaning that the airpump only has one speed-on.

**Raven02ta** · 08-09-2007, 10:21 AM

Originally Posted by 02ultraZ

So it winds down only taking a few seconds, meaning that the airpump only has one speed-on.

Thats correct.

**02ultraZ** · 08-09-2007, 12:24 PM

cool thank for all the help guys.

**02ultraZ** · 08-13-2007, 12:46 PM

Ok update guys, it's not my air pump. I pulled the fuse for the pump the last time it made the noise. It was the same type of scenario too, i drove it for a while and parked it for maybe two hours. Started it and the noise started, i pulled the fuse it didn't stop...I popped the hood and it sounds like its coming from inside the motor! No matter which side of the car i stood on i put my ear right down to the motor and it sounded like it was coming right from the middle of the motor. What do you guys think!?

**02ultraZ** · 08-13-2007, 12:47 PM

It did stop after about 3-4 minutes, i didn't check the temp but should have.

**TACE02** · 08-13-2007, 01:51 PM

not my area of expertise, but from the way you describe it, it sounds like a bearing (cam) possibly or maybe even harmonic balancer. I would hope not the cam bearing though. balancer is quick and easy comparatively and less expensive of a task. good luck, and hopefully it is something easy and inexpensive. also did this just start happening, and if so was it just after an oil change, if so, maybe start there and change oil.