New Tahoe. New problems

[Newkon]

Hey guys

I just bought a 2001 Tahoe for a steal but there are a few issues. When driving the tahoe, it makes a rattling noise. I am not asking what it is based on such little information, but i do believe that it is the flex plate. Are there any troubleshooting procedures to take to ensure that my clutch plate is cracked or bad? The noise is coming from the what seems like the bell housing. It is intermittent though so thats why i think its cracked or warped near the bolts that hold it onto the torque converter.

Also, my AC compressor clutch isn't engaging and it doesn't seem like its getting power to it. I checked the continuity in the relay as well as checked the ac fuses and everything seems to be fine. Are there any steps to figure out where its losing the power?

Thanks!

 

[ISU-152]

Check your exhaust first. Heat shields at the motor and cat

 

[Tonyrodz]

I had to replace the flexplate in my express van, it was cracked almost all the way around. Starting out as a small little tinging sound. My buddy, who's a mechanic kept saying it sounded like a loose cat converter shield. Kept getting louder. Does yours kind of sound like that or something similar.

 

[rockola1971]

Also check for backed out flexplate mounting bolts. AC compressor has a low pressure cutoff in series with the magnetic clutch. The A/C will not engage and start compressing refrigerant if the low side is below a certain PSI. It can be bypassed for a very short time for troubleshooting.

 

[YukonandtheHOE]

I had to replace the flexplate in my express van, it was cracked almost all the way around. Starting out as a small little tinging sound. My buddy, who's a mechanic kept saying it sounded like a loose cat converter shield. Kept getting louder. Does yours kind of sound like that or something similar. View attachment 71838

Haha that is the 5.7 out of my 1990 c2500, never would have known unless i didn't rob the th400 for another project. No noise and pulled a lot of heavy trailer with it lol
I'd never seen that before either

 

[Tonyrodz]

View attachment 71840 Haha that is the 5.7 out of my 1990 c2500, never would have known unless i didn't rob the th400 for another project. No noise and pulled a lot of heavy trailer with it lol

Damn lucky!

 

[YukonandtheHOE]

Lol looking back.. all them Smoke Shows, stoopid lumpy voodoo cam and hard launches.. yah im lucky

Damn lucky!

 

[Newkon]

I had to replace the flexplate in my express van, it was cracked almost all the way around. Starting out as a small little tinging sound. My buddy, who's a mechanic kept saying it sounded like a loose cat converter shield. Kept getting louder. Does yours kind of sound like that or something similar. View attachment 71838

It almost sounds like a bunch of marbles in the exhaust. It is very hard to pin point the source of the sound. I took off the transmission plate to gain access to the flex plate and still couldn't really pin point the sound but it seems to be coming from the bell housing and ricocheting the sound towards the middle of the transmission.

 

[Newkon]

Also check for backed out flexplate mounting bolts. AC compressor has a low pressure cutoff in series with the magnetic clutch. The A/C will not engage and start compressing refrigerant if the low side is below a certain PSI. It can be bypassed for a very short time for troubleshooting.

What is the process for bypassing the low pressure cutoff switch?

 

[mizzouguy]

Its on the drier, unplug it and check for continuity on the switch terminals. I believe it closes the circuit when the pressure is high enough and not the other way around, but you can check first. Anyway, if its normally open and closes with pressure, just jumper wire/paper clip the two terminals in the connector that you unplugged and you can temporarily bypass it. Make sure it doesnt ground to anything and if it fixes it, replace the switch and dont leave the jumper in lol. If its normally open when the system has pressure (which I don't think is the case) you can just leave it unplugged.