So I have a 94 Trans Am with the 5.7L LT1. My issue is a whining/whistling noise. When I get on the throttle more than half way it sounds like a serpentine belt squeal. I used a stethoscope to determine the origin of the noise and it sounded like it was coming from about halfway back of the motor on the driver side where the manifold is. I noticed it had a broke manifold gasket where the manifold meets the motor. I just replaced it this morning. It runs a lot smoother and a little more power now but still have that noise. Anyone have any ideas?
Weird noise on 94 Trans Am
- Thread starter MFCory
- Start date
92 Sunbird LE
Well-known member
Do you have a way to post a YouTube video?
Has the Engine ever been rebuilt?
Doug in P.R.
Has the Engine ever been rebuilt?
Doug in P.R.
cammerjeff
Well-known member
My 1st thought would be an accessory Bearing, either the Alternator or A/C compressor. I would remove the serpentine belt and run the engine up and see if the noise goes away. I would also spine the Alternator by hand to see if it makes any noise or feel rough when turning.
Other than that it could be a water pump, the Opti Spark unit? Or power steering Pump. With 200,000 miles any of the accessories could be going.
Good Luck, and tell us what you find please.
Other than that it could be a water pump, the Opti Spark unit? Or power steering Pump. With 200,000 miles any of the accessories could be going.
Good Luck, and tell us what you find please.
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I know it's not coming from the front of the motor after using a stethoscope to isolate the noise. So far I have figured it is due to an exhaust leak. I will hopefully be spending the day tomorrow tightening it all up after doing a smoke test to the exhaust system and finding multiple leaks.
Update. So the squealing that had many people thinking I had a cheap super charger on my car is gone. It was an exhaust manifold leak. Took me an hour and 10 minutes to do the drivers side and 2 hours to do the passenger side. None of the bolts were tight at all and the one on the passenger side closest to the firewall I took out with my fingers. The gaskets where replaced before seeing as they do not come with them from the factory because they are machine fit so who ever did them thought it was a pain to get to those bolts and left them alone resulting in the gaskets burning out. Just some advice if you decide to tackle this. The drivers side is relatively easy the front 4 do from on top and the back two do from under the car. Leave in the bolt closest to the firewall but loose enough to slide the gasket in. Now the passenger side is a pain. First take the alternator off then use a swivel socket and a 14mm deep well socket for the front bolt and work your way back. My suggestion is to leave the front and the back bolts in because it's a pain to get it all aligned if you don't. Hope someone finds this useful and I'm sorry for carrying on it's late.
92 Sunbird LE
Well-known member
Maybe studs instead of bolts would work better?
Doug in P.R.
Doug in P.R.
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So I'm stuck on the side of the highway as I type this. I was on my way for a 3 hour trip to Augusta, ga from Newnan, ga for my military disability yearly review and my car failed on me. It started yesterday. It starts and idles just fine but when I gave it gas it didn't seem to want to move. So I checked the manifold check valves and they were both blown out so I replaced them and it ran fine. So I started driving it this morning and about 30 mins into my trip it happened again. I'm thinking it a clogged converter. Anyone else have any ideas?
I am getting it towed to work where I can do the fuel pressure test. It has one catalytic converter. I ran the codes yesterday and there wasn't any. I bought the car about 2 months ago and when I looked at the fuel filter it looked fairly new.
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Alright another update. It was my catalytic converter. I got it to my shop, lifted it up, and checked the fuel pressure which was good, then checked the temps of the catalytic converter. Before the cat it was at 700° an the cat itself was at 300°. So I cut the cat off and ordering another and will have it on Monday. So if you have any whistling noise or loss of power definitely check your catalytic converter.