What hose is this? 98 Chevy Silverado 5.7 V8

[AlexHoopes]

Specifically the hard small plastic hose with the elbow

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[east302]

The large elbow is to the PCV valve. The small one below has a hard line across the intake to the passenger side. It connects to a solenoid on the firewall below the accumulator and controls a water valve on the heater lines. The valve closes when the temperature dial is set to the “max” cold detent to maximize a/c performance.

The water valve, solenoid, vacuum line and that dual-line fitting are specific to Tahoe, Yukon and Suburban. Trucks (at least regular and extended cabs) didn’t have them. That fitting would have then only had the one connection at the top to the PCV valve.

Was the original engine swapped?

Edit: version used on pickups...

You must be registered for see images attach

 

[AlexHoopes]

The large elbow is to the PCV valve. The small one below has a hard line across the intake to the passenger side. It connects to a solenoid on the firewall below the accumulator and controls a water valve on the heater lines. The valve closes when the temperature dial is set to the “max” cold detent to maximize a/c performance.

The water valve, solenoid, vacuum line and that dual-line fitting are specific to Tahoe, Yukon and Suburban. Trucks (at least regular and extended cabs) didn’t have them. That fitting would have then only had the one connection at the top to the PCV valve.

Was the original engine swapped?

Edit: version used on pickups...

You must be registered for see images attach

Original engine was swapped, unsure what from as I bought it after it had been swapped, I was told it was out of a GMC Sierra. Would this broken hose cause a vacuum leak that would make idling rough?

edit: just to be clear the broken hose is the small one

 

[east302]

If this is on a truck (no solenoid or water valve in the heater lines) then take the small line off and cap the fitting. It would be a vacuum leak.