This is the correct Vacuum hoses routing for the Volvo 850 TCV (Turbo Control Valve).
The vacuum hoses for the TCV are the first cause of failure when you have boost issues, both lacking boost and overboost.
When replacing the hoses make sure to re-connect them like in the diagram above.
The green hose goes to the nipple on the turbocharger cold side.
The yellow hose to the turbo wastegate.
The blue hose goes to the inlet hose, right after the MAF.
The TCV itself is attached to the air filter housing.
The instructions in this tutorial will work in the following models / years:
– 1997, 1998 Volvo S70
– 1997, 1998 Volvo V70
– 1997, 1998 Volvo C70 Coupe and Convertible / Cabrio
– Volvo 850 T-5 225 hp B5234FT, made / sold in 1994, 1995, 1996 and 1997
– Volvo 850 T-5 R 240 hp B5234T5, made / sold in 1995
– Volvo 850 R 250 hp B5234T4, made / sold in 1996 and 1997
– Volvo 850 R Auto 240 hp B5234T5, made / sold in 1996 and 1997
– Volvo 850 2.3T 218 hp B5234T2, made / sold in 1995, 1996 and 1997
– Volvo 850 2.5T 193 hp B5254T, made / sold in 1997
– Volvo 850 GLT 2.0T 210 hp B5204FST, made / sold in 1994, 1995, 1996 and 1997
– Volvo 850 GLE 2.0T 180 hp B5204T2, made / sold in 1996 and 1997
– Volvo 850 2.0 20V 143 hp B5204FS, made / sold in 1992, 1993, 1994, 1995 and 1996
– Volvo 850 2.0 10V 126 hp B5202FS, made / sold in 1995, 1996 and 1997
– Volvo 850 2.5 20V 170 hp B5254FS LH 3.2, made / sold in 1992, 1993, 1994, 1995 and 1996
– Volvo 850 2.5 20V 170 hp B5254FS, made / sold in 1996 and 1997
– Volvo 850 2.5 10V 144 hp B5252FS, made / sold in 1993, 1994, 1995, 1996 and 1997
– Volvo 850 2.3 20V 144 hp B5234FS, made / sold in 1994, 1995, 1996 and 1997