1990 XJS Firewall Vacuum Question
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From: Florida
1990 XJS Firewall Vacuum Question
I have a 1990 XJS and need help with understanding the
climate control vacuum routing.
I have three vacuum hoses coming off the passenger side
firewall into the engine compartment. Two black hoses, one
with a check valve on it and the third hose is a red.
All the vacuum charts I've seen for the car show two hoses of
f the passenger side firewall - one for the climate control
vacuum off the back of the intake manifold on the A side and
the other hose going to the heater control valve.
Could anyone shed light on where each of these three hoses
go-
1. red hose
2. black hose with check valve
3. plain black hose
Thanks,
Peter
climate control vacuum routing.
I have three vacuum hoses coming off the passenger side
firewall into the engine compartment. Two black hoses, one
with a check valve on it and the third hose is a red.
All the vacuum charts I've seen for the car show two hoses of
f the passenger side firewall - one for the climate control
vacuum off the back of the intake manifold on the A side and
the other hose going to the heater control valve.
Could anyone shed light on where each of these three hoses
go-
1. red hose
2. black hose with check valve
3. plain black hose
Thanks,
Peter
Joined: Sep 2010
Posts: 2,114
Likes: 976
From: Indianapolis, IN
1. red hose
small red plastic vacuum hose goes from rear of RH intake manifold to the Marelli Ignition ECU at the base of the RH "A" pillar.
2. black hose with check valve
black side of the check valve [should be black hose w/white trace] goes to vacuum tee that splits and goes to the RH manifold and to the round, bluish full load vacuum switch at top rear of intake manifold.
3. plain black hose
probably the hose to the heater water valve at center of firewall
Cheers,
small red plastic vacuum hose goes from rear of RH intake manifold to the Marelli Ignition ECU at the base of the RH "A" pillar.
2. black hose with check valve
black side of the check valve [should be black hose w/white trace] goes to vacuum tee that splits and goes to the RH manifold and to the round, bluish full load vacuum switch at top rear of intake manifold.
3. plain black hose
probably the hose to the heater water valve at center of firewall
Cheers,
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