Hello Everyone
I can not afford to do the job 2 or 3 times.
Cost benefit analysis says:
Replace all vacuum hose and T on the 20 year old car at first opportunity.
A roll or two of hose and enough Ts to do the entire car is cheap, at least it is when compared with time loss or elevated blood pressure.
With caution and patience; the R&R is a one weekend permanent fix.
I use a razor to cut off one hose at a time; and keep 20 rolls of electrical tape and 500 zip ties in stock at home, all the time, just for jobs like this.
Use a straight union and tape to join the old and new hose; pull the old hose out and the new one in at the same time.
Then all you need to diagnose in the future is vacuum motors and switches.
The aftermarket hose should be good for 10 years.
Have a great day.

__________________
ASE Master Mechanic
https://whunter.carrd.co/

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
2003 Volvo V70

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