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1994 Volvo 850 Anomaly - VVIS, vacuum, EGR, PCV, confused

Help, Advice and DIY Tutorials on Volvo's extremely popular car line -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, 850 R, 850 T5-R, 850 T5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

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erikv11
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erikv11

Re: 1994 Volvo 850 Anomaly - VVIS, vacuum, EGR, PCV, confused

Post by erikv11 » Tue Feb 16, 2016 10:44 pm

So, the mystery part is just the EGR solenoid, or does the car have the round type of EGR solenoid too?

Turning on the heater draws a pretty big electrical load. There are two basic suspects. First is/are the major elements of the charging system: the battery, the connections at the battery, the battery cables, the alternator. First step is definitely to clean the connections to the battery and the attachments of the grounds, and check the cable ends for deterioration and if they get hot under usage.

The second group of key suspects are the blower motor and the blower motor resistor. Does it have ECC or MCC? If the blower is seizing then it will draw too much power, fry the resistor, etc. A dying blower motor usually gets noisy but not always.

Oh, there are also all kinds of weird electrical behaviors when the ignition switch is failing. This isn;t one of the usual ones, but you should just rule it out: when the car is running and you jiggle the key, does the car's electrical go crazy in any way (lights on the dash on/off, car stumbles, etc)?
'95 854 T5-R, Motronic 4.4, 185k
'96 855 NA, 145k
'98 S70 NA, 220k (living out west)
'98 V70, T5 tune-injectors-turbo, LPT engine, 286k
'06 S60 R, 167k
'99 Camry V6 :shock: 125k
gone: '96 NA 850 210k, '98 NA V70 182k

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firestarterpro
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Re: 1994 Volvo 850 Anomaly - VVIS, vacuum, EGR, PCV, confused

Post by firestarterpro » Wed Feb 17, 2016 5:10 am

Hey, i currently have a 94 with an EGR ive successfully fixed, albeit on multiple instances. Nonetheless, it seems youve come to some sort of conclusion, however I advise you to compare the valve to the one on the air box. The previous owner may have tried to fool the EGR by adding a duplicate near the vacuum controller (which often throws an erroneous check engine code when the EGR system is dirty). I say this mostly because Ive seen a 93 volvo 850 and it was just like mine under the hood.

Not sure about the heater problem, hopefully someone else will chime in.
._____________,
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The proudest owner of a Naturally Aspired 2.4L Volvo 850 Wagon of 1995!!! :o :o :o
94 850 NA Wagon was hit and totalled at 350k :oops:
96 850 NA Sedan sold at 180k :arrow:
95 850 Turbo Wagon sold at 260k for parts :!:
95 850 NA Wagon sold at 220K :arrow:

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erikv11
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Re: 1994 Volvo 850 Anomaly - VVIS, vacuum, EGR, PCV, confused

Post by erikv11 » Mon Feb 22, 2016 1:41 pm

Just to follow up for others who may come upon this thread down the road: The "mystery" part looks like it is just a standard SAS solenoid.

If the car has SAS, then the purple line runs to the SAS valve, one port should be capped off, and the other port runs to the vacuum tree through a check valve. Like these, the white line is going to the vacuum tree:
image1.JPG
SAS solenoid in place, 97 GLT
dscn2344.jpg
generic SAS solenoid, 850
The nipple on the SAS solenoid toward the battery side, is just capped off.

To my knowledge that solenoid has no business being in a 94 like the OP stated he has, that year had EGR but never SAS. EGR and SAS are never together in the same car. So the car has some Frankenstein to it, but a lot of them do ... :D
'95 854 T5-R, Motronic 4.4, 185k
'96 855 NA, 145k
'98 S70 NA, 220k (living out west)
'98 V70, T5 tune-injectors-turbo, LPT engine, 286k
'06 S60 R, 167k
'99 Camry V6 :shock: 125k
gone: '96 NA 850 210k, '98 NA V70 182k

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abscate
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Re: 1994 Volvo 850 Anomaly - VVIS, vacuum, EGR, PCV, confused

Post by abscate » Tue Mar 10, 2020 5:41 am

Bump to thread on Volvo Variable Intake System VVIS used on 1993-1995 cars

This adds to the list of vacuum controlled stuff on Volvos

PCV Purge
Evap Purge
Cruise control (sneers from 1999 2000 aside)
Hot air door motor on air cleaner (non turbo only)
Supplemental Air System (cold start pump for exhaust manifold)
EGR valve and solenoid
VVIS
TUrbo CBV pull off
Shrimp Vacuum

.....I think thats it...
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