loud "cold" start gone?

[BigSky]

I've had the ZR2 w/borla (dealer installed before p/u) since early June. Up until recently (10 days), it had the obnoxiously loud "cold" start but w/temps now in the 10-20F, loud cold start is gone. I like it this way but any ideas on the why?? Anyone else experiencing the same?

 

[22ZR2]

Mine is the same, I have the AWE catback. When I start it lately it has way less of a bark....my lady even said "your truck doesn't sound as mean" have no idea why tho

 

[Roccos_Van]

I've had the ZR2 w/borla (dealer installed before p/u) since early June. Up until recently (10 days), it had the obnoxiously loud "cold" start but w/temps now in the 10-20F, loud cold start is gone. I like it this way but any ideas on the why?? Anyone else experiencing the same?

I noticed the same thing. About 10 days ago it stopped the cold starts. I have the afe replacement muffler.

 

[22ZR2]

That is so odd, I wonder if there was an update or something? It was like 1 day it was loud af, then the next morning not even close

 

[sshurtleff]

AWE. Same for me.

 

[22ZR2]

Ok that's just odd.....ill check my recent updates and see if there is anything. Seems to suspicious with all of us experiencing this

 

[KDelta]

Ok that's just odd.....ill check my recent updates and see if there is anything. Seems to suspicious with all of us experiencing this

Do you all live on the north? South? Climate would be a weird reason but at what temperature does this quiet down?

 

[22ZR2]

I live in northern Utah, seemed about 40 or less

 

[Smokey0844]

Mine didn’t do it until the temp dropped below freezing. 34 degrees = loud. 27 degrees = quiet?

 

[likeitsmyjob]

Mine didn’t do it until the temp dropped below freezing. 34 degrees = loud. 27 degrees = quiet?

Same here. It was single digits this weekend and it is way quieter than it has been all summer. The rpm's at start up are quite a bit lower than when its warm out. Just have muffler delete

 

[KDelta]

Funny, I thought it would be when the weather is cold, it gets louder.

 

[22ZR2]

Strange that the RPM is lower in colder weather. I wonder what is going on in the engine management to warrant this

 

[BigSky]

Strange that the RPM is lower in colder weather. I wonder what is going on in the engine management to warrant this

Seems assbackwards.

 

[Smokey0844]

Back above freezing this morning. Hit the remote start and there’s the roar again. It did drop rpm’s pretty quick (3 seconds after start) but it did sound normal on start up. I have noticed this truck gets up to temp a lot faster than my TB did. I’m now wondering if there’s valve or two that closes in the exhaust system when the truck senses sub freezing temps.

 

[KDelta]

Back above freezing this morning. Hit the remote start and there’s the roar again. It did drop rpm’s pretty quick (3 seconds after start) but it did sound normal on start up. I have noticed this truck gets up to temp a lot faster than my TB did. I’m now wondering if there’s valve or two that closes in the exhaust system when the truck senses sub freezing temps.

That'd be something. BTW, due to our politicians driving the dollar into the dirt, I have been thinking of getting a 22 TB in Glacier and nixing the ZR2. Thoughts on performance diff. Should I stretch and make the Z happen? Is it that much better? This will be my first off-road beast. I have a Z71 Silverado. Clearly not the same category.

 

[Smokey0844]

I had a 19 TB with every option available on it. Loved the truck. Except that the transmission was a loaded ticking time bomb. I decided to replace it and quickly found out just how much prices have increased. The turning point for me was when I saw what else I got with the ZR2 vs TB compared to the price difference. IMO enough can’t be said about the suspension alone between the two. Another thing to consider is once things go back to normal (lol) that the TB will be a lot more common and therefore have a mark against it on the resale side. I paid a lil under msrp for the ZR2 and it’s quoting about 10k over msrp on kbb for what that’s worth. I’m happy with the call I made and that’s from someone who didn’t expect to get rid of the TB to begin with.

 

[landpilot]

That'd be something. BTW, due to our politicians driving the dollar into the dirt, I have been thinking of getting a 22 TB in Glacier and nixing the ZR2. Thoughts on performance diff. Should I stretch and make the Z happen? Is it that much better? This will be my first off-road beast. I have a Z71 Silverado. Clearly not the same category.

The suspension and locking differentials are definitely worth the difference to me. My son has a Trail Boss LT, and the ZR2 seems more like a High Country with an off road suspension. I live in rural KY and I can fly down the back roads without any problem - the same roads seem to really upset my wife's BMW x3 so she usually likes to take my truck lol...

There's a post on here from a dealer in MI who is selling at supplier price, but if you're in MA, not sure that would work because of the emissions regulations, but it could be worth a look to save you some money. He's got 3 Glacier Blue that are due in December.

(edited to correct pricing info)

 

[22ZR2]

Back above freezing this morning. Hit the remote start and there’s the roar again. It did drop rpm’s pretty quick (3 seconds after start) but it did sound normal on start up. I have noticed this truck gets up to temp a lot faster than my TB did. I’m now wondering if there’s valve or two that closes in the exhaust system when the truck senses sub freezing temps.

That is odd, But I think you are on to something with an exhaust valve to help it warm faster. I am not a GM tech so I cant say unfortunately