LBZ blow by?

06DDLBZ

New member
Mar 13, 2017
34
0
0
Hello everyone

When riding in the truck I can hear a swooshing sound, when going down the interstate I feel like I can hear it more. I do not have any seat time in the truck. I rebuilt the truck 100% after it flooded. I got a stock engine from California low mileage very clean wasn’t deleted and put on a gt3794 and y bridge. The truck has a pcv reroute. I had a buddy get under the truck to identify a tapping sound that turned out to be the exhaust hitting the frame. He said a little bit of white smoke was coming from the passenger side pcv tube when he was down there while I was giving it gas. It clicked in my head the sound going down the interstate could be the pcv tube? It sounds fine while driving around the neighborhood at lower speeds.

When I got home, I popped the oil cap and I could barely see any white smoke. I had to tilt my head to even really see it. I pulled both pcv tubes on top the engine and both are barely emitting any white smoke. When I say barely I mean you really have to look at them. I then turned the oil cap upside down and it doesn’t move off the oil filler neck.

Truck has no rough starts or rough idle. On a tech2 the truck requested idle is 680 and it sticks around 680/681.

With the truck in park I looked at the injector balance rates and this is what they are:

Main injection timing -1.9

1:-0.2
2:1.0
3:-1.0
4:-2.8
5:0.0
6:1.6
7:1.9
8:-0.4

Any ideas if this is normal?
 
Last edited:

DAVe3283

Heavy & Slow
Sep 3, 2009
3,680
236
63
Boise, ID, USA
The blow by amount sounds normal. The "swooshing" sound could be the turbo making turbo noises, or it could be a boost or exhaust leak. It would be worth checking over the boost tubes to make sure they don't have any holes rubbed through them.
 

steelbird312

New member
Jan 23, 2014
2
0
0
Dont know if you have addressed your swooshing sound. Just this past week, I had a similar sound I first noticed on a 400 mile quick trip. Just as I finished the trip, the alternator gave up. Just a thought.
 

06DDLBZ

New member
Mar 13, 2017
34
0
0
I did a boost test leak and identified the issue. The hex screw on the wcfab y bridge pipe had backed out some and that’s what the sounds was. I tightened it back up and it’s good to go now. Also replaced all my trans lines- talk about a messy job. Amazon was the same price on the lines as rock auto with free prime shipping.