Scania Straight 6 Engine Sound

[Space_Night]

the compressor @supersobes is actually mechanically connected to the engine, so as soon as you fire up the engine the compressor is running as a result whether you're idling with the brakes on, or meandering down the highway the compressor is charging the system and so every so oftem the check valve has to open otherwise the system will overpressurise and blow an airline at best or blow a tank up at worse.

[supersobes]

I am aware of how the air compressor works. What I mean by it's not connected to engine is that in terms of the game sounds, the engine audio and the air cutoff sound are two separate sound files that are activated and defined by two different parameters. The air cutoff sound should not be in the loaded engine sound, which is simply the sound that the engine makes when the throttle is being applied.

[scaniadriver01]

the compressor on a real life scania doesnt run full time..
it has an electro magnetic pully.. when it needs to build up pressure it running.. like when it gets under 8 bars of pressure...
and when its at 10 to 12 bars of pressure it cuts off.. then you would hear a blowoff noise when your are stationairy but when your driving you normally cant hear it because of the driveline noise, wind noise and other traffic around you.. and possibly your radio
this is done to increase efficiency.. everything thats driving by the engine.. like the air compressor, AC compressor.. it all makes the engine use diesel.. so they disconnect those parts when they are not needed so the engine uses less diesel...

[Space_Night]

i thought it was permanently coupled, as opposed to an electromagnetic coupling

[scaniadriver01]

almost the same as the coupling on your AC compressor.. but the ECU controlles the on and off function..
when your driving on CC at 90 km/h your not using much air.. other then slight adjustments from the airsuspention and cab suspention.. your not using the brakes or anything that uses a lot of airpressure... so there is no need to run a compressure full time..
the compressor is usually located under the left side of the cab infront of the wheels with the air cooler.. as compressed air heats up.. so it gets cooled down before its dried through a filter before its stored in the airtanks or used throughout the airsystem..

[scaniadriver01]

[ external image ]wallpapers_scania_engines_1_b
red circle = the air compressor
blue circle = the aircooler

[ external image ]9325001100
then air passed through one of these filter.. the filter is hidden within the chassis rails for easy access as these filters need to be replaced with every service ( around 6 months or 60.000 km) and from there it goes through valves etc for components as brakes, airsuspention, suspention for the cab, suspention for the driver ( and passenger) seat, brakes and suspention for the trailer or trailers if you pull a double...

i tried to become a truck mechanic.. but i failed on a few classes.. also on the final for the air system... the air circuit of a truck is (very) difficult and intense to learn...

[supersobes]

This issues still occurs on version 1.37.1.82 that was released today.

[Space_Night]

just a thought.

when the sound occurs, do the revs fall back?

1500RPM "TSSSSSS" 1000RPM ?

[supersobes]

Nope. They just keep repeating over and over again at the same time intervals as the sound file is looping. As shown in my video, it happens when driving at a constant speed.

[supersobes]

This bug still occurs on version 1.38.

Date of Bug Report: 26 Jun 2020
Game Version: 1.38.0.18s
No Mods
Always Reproducible

game.log: