Very high pitched whine/scream coming from engine block
#1
Very high pitched whine/scream coming from engine block
I have a 95 Camaro z28 with v8 5.7 lt1. When I start the car it whines/screams really loud... It also idles real high.
I just bought it and had to replace the floor shifter IE... It was stuck in 1st and the **** was broken. I replaced the tensioner pulley and removed the belt and it still does it... The mass air flow hose is a little worn and the IAC sensor was broken off... Any Idea on what could be making this noise?
I just bought it and had to replace the floor shifter IE... It was stuck in 1st and the **** was broken. I replaced the tensioner pulley and removed the belt and it still does it... The mass air flow hose is a little worn and the IAC sensor was broken off... Any Idea on what could be making this noise?
#4
Re: Very high pitched whine/scream coming from engine block
The IAC is not a "sensor".... it's an actuator that controls idle speed by moving a pintle in and out of the idle air passage. Did you replace it? What are you calling the MAF "hose".... do you mean the rubber inlet elbow? Does it have any holes or cracks in it?
When you start the engine cold, the PCM raises the idle RPM based on the coolant temperature. How fast does it idle? Does it slow down as the coolant temperature increases? Possible there's a damaged CLT sensor.
Is the AIR pump working? It will make a lot of noise if it's badly corroded.
When you start the engine cold, the PCM raises the idle RPM based on the coolant temperature. How fast does it idle? Does it slow down as the coolant temperature increases? Possible there's a damaged CLT sensor.
Is the AIR pump working? It will make a lot of noise if it's badly corroded.
#5
Re: Very high pitched whine/scream coming from engine block
The IAC is not a "sensor".... it's an actuator that controls idle speed by moving a pintle in and out of the idle air passage. Did you replace it? What are you calling the MAF "hose".... do you mean the rubber inlet elbow? Does it have any holes or cracks in it?
When you start the engine cold, the PCM raises the idle RPM based on the coolant temperature. How fast does it idle? Does it slow down as the coolant temperature increases? Possible there's a damaged CLT sensor.
Is the AIR pump working? It will make a lot of noise if it's badly corroded.
When you start the engine cold, the PCM raises the idle RPM based on the coolant temperature. How fast does it idle? Does it slow down as the coolant temperature increases? Possible there's a damaged CLT sensor.
Is the AIR pump working? It will make a lot of noise if it's badly corroded.
Yes I replaced both the sensor and the actuator on the side of the throttle and just noticed that the relay fuse for the air pump looked kinda weird... Ima replace it and see how it goes. If not I'm gonna check the air pump itself out... Thanks bro I'll post a video if it still squeals...
#6
Re: Very high pitched whine/scream coming from engine block
Here's the video of the sound it makes... I'm kinda thinking that the access oil somebody put in burned out the engine bearings... So ima crack it open and see what I could find
Last edited by Nighttrainxprss; 08-08-2016 at 10:15 PM.
#8
#9
95 Camaro z28 5.7 lt1
Ok so i contacted the previous owner and got some info... He says that the shifter cable went bad and the car was stuck in 1st gear... My question is what would go bad causing a loud screech/scream/whine? Could it be the clutch? Or cam bearings? Automatic transmission... Help me out please
Last edited by Nighttrainxprss; 08-15-2016 at 03:28 PM.
#10
Re: 95 Camaro z28 5.7 lt1
Wrong forum.... the thread you started earlier about this is in the "LT1 Based Engine Tech" forum. I'll try and merge this post with that thread, so it makes sense. Might want to clarify which trans your car has. Only the auto trans has a "shifter cable". Only the manual trans has a "clutch".
#12
Re: Very high pitched whine/scream coming from engine block
Yes... The noise is coming from inside the heads or cam somewhere... Im pulling the heads tomorrow to see if anything looks worn... Looks like im doing a full rebuild after all SMH
#13
Re: Very high pitched whine/scream coming from engine block
#14
Re: Very high pitched whine/scream coming from engine block
As has been suggested the WP or Opti (cap getting contact from rotor) may be the cause.
Hard to follow your threads...but I think you mentioned something about the air pump. It should only run for around a minute on initial cold start up...doubtful it is the air pump but unplug it to confirm it is not source of noise.
pulling heads is not really going to reveal much regarding noise if it is internal engine. The rod, crank or cam bearings failing would leave metal flakes in the oil if that is what is causing the screeching noise
Maybe your WP impeller is making contact with the WP housing...you could easily tell by removing the front cover from it or removing WP and spinning the spline shaft
you need to do more specific diagnostics before tearing apart the motor
#15
Re: Very high pitched whine/scream coming from engine block
Just replaced the opti with a jeg and completely disregarded the water pump when i seen that it was gear driven and not belt driven... But i removed a bunch of stuff already so ima take it out and inspect it...