Weird sounds

**98TransAmWs-6** · 07-15-2011, 12:02 PM

After installing my Intake manifold and removing the egr/air from the car I have this weird high pitched whiney sound when I push on the gas pedal. When I press the pedal lightly to a certain point it makes the sound but if I lay off it goes a way and if I push harder it goes away (or at least I can't hear it anymore over the car), it is very faint and hard to hear. I also get this other weird noise when going slow and it only happens when the wheel is turning but it isn't consistant when it does happen, it is hard to describe what it sounds like but it is a slower sound that is coming from my drivers side area by the wheel (at least that is where it sounds like when I am driving). My mods are LTs, Catted y-pipe, 96mm Intake manifold /101mm TB, 4" Fernco coupler, Volant airbox, Highflow fuel rails, !EGR/!Air, and I put new 20x8 and 20x10 wheels on (not sure if that matters). My differiental is leaking, would that cause any of these noises? Also would the Air pump cause that too, since I haven't had it actually deleted yet? Any idea what the sounds might be might be?

**cammed goat** · 07-15-2011, 03:29 PM

My guess is the air pump is active. Second noise most likely is your diff since you stated it is low. How bad is the leak? Are you leaving small puddles in parking spaces? A member did an AIR delete and he disconnected the pump. I can't find the thread at the moment.

**98TransAmWs-6** · 07-15-2011, 04:03 PM

Originally Posted by cammed goat

My guess is the air pump is active. Second noise most likely is your diff since you stated it is low. How bad is the leak? Are you leaving small puddles in parking spaces? A member did an AIR delete and he disconnected the pump. I can't find the thread at the moment.

So would disconnecting the air pump fuse stop the noise? Does the gas pedal have anything to do with the air pump, as it only makes the sound while goving it a little gas?
Also with the second sound, it has been leaking for a while so why would it now make a noise? Although it has been sitting for few weeks, and yes it does leave small puddles in my garage.

**cammed goat** · 07-15-2011, 04:15 PM

I cannot be certain on the AIR system as I am not familiar with it. PCM could possibly activate it when throttle is pressed to send fresh air into the intake. Others will chime in to correct me.

If your rear is leaking, and you haven't filled it, then, most likely your rear is letting you know it is on its way out.

**98TransAmWs-6** · 07-15-2011, 05:39 PM

Originally Posted by cammed goat

I cannot be certain on the AIR system as I am not familiar with it. PCM could possibly activate it when throttle is pressed to send fresh air into the intake. Others will chime in to correct me.

If your rear is leaking, and you haven't filled it, then, most likely your rear is letting you know it is on its way out.

Well I guess I will start with removing the air pump fuse and then fixing the leak and refilling the rear and see if that helps at all.

**cammed goat** · 07-15-2011, 06:12 PM

Let us know how you make out. The rear might quiet down some, but if you have been driving on low gear oil for a long period of time, there isn't much time on that rear.

**vette&ws6** · 07-16-2011, 06:27 AM

I think I can help you with the first noise. It's not the AIR pump, that only runs when the car is first started to pump air into the exhaust manifolds to reduce emissions. The noise you are hearing at part throttle is the air disturbance as it enters your motor through the modified air intake tract. The bigger throttle body and intake manifold can make a harmonic (whistle) at certain rpm's that can be VERY noticeable. Due to the modifications you have made to the car, this noise will likely be inherent to it from this day forward. As far as the other noise from your wheel...could be many different things. Is the noise from the front or rear. One possibility: Might be coming from your brakes if you have some bearing wear in the hub, the flex and load you put on the wheel might be causing a rubbing of the rotor on a caliper bracket. I have seen this issue before, inspect front suspension, brakes, and bearings....This is only one possibility. Could also be your tire/wheel rubbing on the inner fender well or frame....check for witness marks.

**98TransAmWs-6** · 07-16-2011, 01:33 PM

Originally Posted by vette&ws6

I think I can help you with the first noise. It's not the AIR pump, that only runs when the car is first started to pump air into the exhaust manifolds to reduce emissions. The noise you are hearing at part throttle is the air disturbance as it enters your motor through the modified air intake tract. The bigger throttle body and intake manifold can make a harmonic (whistle) at certain rpm's that can be VERY noticeable. Due to the modifications you have made to the car, this noise will likely be inherent to it from this day forward. As far as the other noise from your wheel...could be many different things. Is the noise from the front or rear. One possibility: Might be coming from your brakes if you have some bearing wear in the hub, the flex and load you put on the wheel might be causing a rubbing of the rotor on a caliper bracket. I have seen this issue before, inspect front suspension, brakes, and bearings....This is only one possibility. Could also be your tire/wheel rubbing on the inner fender well or frame....check for witness marks.

My tire is not rubbing on anything, neither is the caliper or bracket. If it was really my brakes wouldn't I hear it while braking? It sounds like it is coming from the front but I don't always hear it for some reason. I haven't heard it in a while. I don't know if this is related but occasionally, when I turn I get a sqeak or whine. That whistling sound, is there no way to get rid of it, well that's annoying. Why is it only at part throttle?

**vette&ws6** · 07-16-2011, 05:43 PM

The whistling noise is generated from the throttle body. It is an air disturbance. After the throttle blade gets past a certain point there is enough gap that the whistle goes away. For example...if you whistle with your mouth and then try to wistle with your mouth open it can't be done. Same thing with your engine. You changed the dynamics of the intake air flow. GM spends a lot of engineering time trying to eliminate this exact problem (hence the wierd looking air intake bellows). The aftermarket does not engineer intake components to be silent, they engineer them to make more power.

**vette&ws6** · 07-16-2011, 05:48 PM

Are you sure your other noise isn't coming from your power steering pump? Sit in one spot, bring rpm's up to about 2000-2200 rpm and turn steering wheel back and forth. Listen for the noise.

**98TransAmWs-6** · 07-16-2011, 08:30 PM

Originally Posted by vette&ws6

Are you sure your other noise isn't coming from your power steering pump? Sit in one spot, bring rpm's up to about 2000-2200 rpm and turn steering wheel back and forth. Listen for the noise.

I was thinking that, wondering if this is the same problem or a different problem
I'll try and do that later today, it appears to only make the sound when warmed up but not every time o turn the steering wheel. If it was the power steering pump would it do it a lot more often?

**vette&ws6** · 07-17-2011, 05:47 AM

Power steering pump noise can be very erratic/intermittent and can be related to heat. Also, check the fluid level and condition.

**98TransAmWs-6** · 07-19-2011, 05:19 AM

Well I changed my differential fluid and fixed the leak. Going to see if it helped at all and then check the power steering fluid/ pump out if it didn't.

**98TransAmWs-6** · 07-19-2011, 06:31 AM

Ok I took a video of the sound by the wheels, it is hard to hear from the video.

http://static.photobucket.com/player...719_101146.mp4

Is that the brakes? Or power steering pump?

**vette&ws6** · 07-19-2011, 08:53 AM

I'm sorry, I could not hear anything in that video.

***SMWS6TA*** · 07-19-2011, 09:08 AM

Since you are a fellow 98' like me you may not know about this TSB. It could be the cause of the noise you are talking about.

Bulletin No.: 87-61-23

Date: May, 1998
Subject:
Accessory Belt Noise/Squeal
(Diagnose/Replace Applicable Part) Models:
1998 Chevrolet Camaro
1998 Pontiac Firebird
with 5.7L V8 Engine (VIN G - RPO LS1) Condition
Some owners of the above listed vehicles may comment on an accessory drive belt slip, squeal and/or squeak.
Cause
This condition may be caused by one, or all of the following:

^	Incorrect Power Steering Pump Pulley installed.
^	Incorrect Main Accessory Drive Belt routing.
^	Main Accessory Drive Belt not centered in all accessory pulleys. (Ribs in belt not lined up with groves in the pulleys.)
^	Harmonic Balancer positioned too close to the engine. This may be caused by the engine side of the Harmonic Balancer Hub being mis-machined.

Correction
Check to ensure the vehicle has the correct P/S Pump Pulley (Correct P/N is 12559885). The part number appears on the web of the pulley in raised characters. This pulley is all plastic except for the inner hub that is connected to the P/S Pump Shaft. If the incorrect pulley is installed, replace the pulley along with a new Main Accessory Drive Belt. Use part numbers listed.
If the Main Accessory Drive Belt is not centered in all pulleys, check for proper alignment of all the accessory pulleys. If all pulleys are aligned, replace the Main Accessory Drive Belt and center the belt in all the pulleys.
At the Harmonic Balancer, the Main Accessory Drive Belt may be tracking too far rearward (approximately 3 mm, 1/8 in.) in relationship to all other pulleys.
If this condition is present, replace the Harmonic Balancer and Harmonic Balancer Bolt along with the Main Accessory Drive Belt and the A/C Compressor Drive Belt. All part numbers are listed.
Important: If it is determined there is a Main Accessory Drive Belt, or A/C belt noise coming from the Harmonic Balancer area it is highly likely the Harmonic Balancer needs to be replaced. Parts Information

Part Number Description 12559885 P/S Pulley 12557562 Accessory Drive Belt 12553118 Harmonic Balancer 12557840 Harmonic Balancer Bolt 12559327 A/C Compressor Drive Belt

**98TransAmWs-6** · 07-19-2011, 10:20 AM

Originally Posted by SMWS6TA

Since you are a fellow 98' like me you may not know about this TSB. It could be the cause of the noise you are talking about.

Bulletin No.: 87-61-23

Date: May, 1998
Subject:
Accessory Belt Noise/Squeal
(Diagnose/Replace Applicable Part) Models:
1998 Chevrolet Camaro
1998 Pontiac Firebird
with 5.7L V8 Engine (VIN G - RPO LS1) Condition
Some owners of the above listed vehicles may comment on an accessory drive belt slip, squeal and/or squeak.
Cause
This condition may be caused by one, or all of the following:

^	Incorrect Power Steering Pump Pulley installed.
^	Incorrect Main Accessory Drive Belt routing.
^	Main Accessory Drive Belt not centered in all accessory pulleys. (Ribs in belt not lined up with groves in the pulleys.)
^	Harmonic Balancer positioned too close to the engine. This may be caused by the engine side of the Harmonic Balancer Hub being mis-machined.

Correction
Check to ensure the vehicle has the correct P/S Pump Pulley (Correct P/N is 12559885). The part number appears on the web of the pulley in raised characters. This pulley is all plastic except for the inner hub that is connected to the P/S Pump Shaft. If the incorrect pulley is installed, replace the pulley along with a new Main Accessory Drive Belt. Use part numbers listed.
If the Main Accessory Drive Belt is not centered in all pulleys, check for proper alignment of all the accessory pulleys. If all pulleys are aligned, replace the Main Accessory Drive Belt and center the belt in all the pulleys.
At the Harmonic Balancer, the Main Accessory Drive Belt may be tracking too far rearward (approximately 3 mm, 1/8 in.) in relationship to all other pulleys.
If this condition is present, replace the Harmonic Balancer and Harmonic Balancer Bolt along with the Main Accessory Drive Belt and the A/C Compressor Drive Belt. All part numbers are listed.
Important: If it is determined there is a Main Accessory Drive Belt, or A/C belt noise coming from the Harmonic Balancer area it is highly likely the Harmonic Balancer needs to be replaced. Parts Information

Part Number Description 12559885 P/S Pulley 12557562 Accessory Drive Belt 12553118 Harmonic Balancer 12557840 Harmonic Balancer Bolt 12559327 A/C Compressor Drive Belt

I will look into that but wouldn' it make the sound more than i the wheels are moving slowly, like at idle and different speeds and even if the car isn't warmed up.

***SMWS6TA*** · 07-19-2011, 12:06 PM

Got one more for you. If you want the parts numbers I got em let me know

BULLETIN NUMBER:
00-06-01-008 SECTION:
06 - Engine/Propulsion System DATE:
March 2000 TECHNICAL
SUBJECT:
Accessory Drive Belt Squeak/Chirp Noise (Install New Double Row Idler Pulley, Generator Bracket and Serpentine Belt) MODELS:
1998-2000 Chevrolet Camaro
1998-2000 Pontiac Firebird
Built Prior to VIN Breakpoint Y2107225 with 5.7L V8 Engine (VIN G - RPO LS1) CONDITION
Some customers may comment on a squeak/chirp noise coming from the accessory drive serpentine belt. The noise will be most noticeable at idle and low engine speeds. CAUSE
The serpentine belt squeak/chirp noise may be caused by misalignment between the idler pulley and crankshaft pulley. A slight rocking motion of the idler pulley causes the misalignment, which results in noise. CORRECTION
To correct this condition on vehicles built prior to the above VIN breakpoint, instal the new generator bracket, double row idler pulley and serpentine belt following Service Manual procedures.

**JayTA98** · 07-19-2011, 12:35 PM

Originally Posted by SMWS6TA

Got one more for you. If you want the parts numbers I got em let me know

BULLETIN NUMBER:
00-06-01-008 SECTION:
06 - Engine/Propulsion System DATE:
March 2000 TECHNICAL
SUBJECT:
Accessory Drive Belt Squeak/Chirp Noise (Install New Double Row Idler Pulley, Generator Bracket and Serpentine Belt) MODELS:
1998-2000 Chevrolet Camaro
1998-2000 Pontiac Firebird
Built Prior to VIN Breakpoint Y2107225 with 5.7L V8 Engine (VIN G - RPO LS1) CONDITION
Some customers may comment on a squeak/chirp noise coming from the accessory drive serpentine belt. The noise will be most noticeable at idle and low engine speeds. CAUSE
The serpentine belt squeak/chirp noise may be caused by misalignment between the idler pulley and crankshaft pulley. A slight rocking motion of the idler pulley causes the misalignment, which results in noise. CORRECTION
To correct this condition on vehicles built prior to the above VIN breakpoint, instal the new generator bracket, double row idler pulley and serpentine belt following Service Manual procedures.

you had this issue scott?

***SMWS6TA*** · 07-19-2011, 12:49 PM

I think I do. It explains this annoying squeak I have. I've already replaced the a/c and belt tensioners and that fixed the loud one. But ever since I fixed/rebuilt my PS pump it's been making the low squeal that seems like only I can hear it.

From what I read on the 99< they changed the bracket on the alternator and gave it a 2mm shift. When the 98's get the the new serpentine belts it now rubs and cause the minor squeal noise because of the 2mm shift in alinement.

It's funny how year one cars have some issues while later years either have none or more then the year one model. I'd take this one over the sail panel issue every time.