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PCV Virgin, PCV system is completely clean but still smokes

Help, Advice and DIY Tutorials on Volvo's P80 platform cars -- Volvo's 1990s "bread and butter" cars -- powered by the ubiquitous and durable Volvo inline 5-cylinder engine.

1992 - 1997 850, including 850 R, 850 T-5R, 850 T-5, 850 GLT
1997 - 2000 S70, S70 AWD
1997 - 2000 V70, V70 AWD
1997 - 2000 V70-XC
1997 - 2004 C70

This topic is in the MVS Volvo Repair Database » PCV is Clean but Still Smokes
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jblackburn
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Re: PCV Virgin, PCV system is completely clean but still smo

Post by jblackburn »

https://www.matthewsvolvosite.com/forums ... =4&t=29837

Into the intake manifold just means sucking it into the vacuum tree. It will clean the top end of your engine - cylinders, valve, carbon buildup, etc.

Some say that it helps restore compression as well. My car did feel a bit more spunky around town afterwards.

For the long startup - do you have fuel pressure after it sits for a few hours, or when the key is flipped to position II after sitting for a few hours without trying to start the engine? My car has always started on the 2nd or 3rd revolution.
'98 S70 T5
2016 Chevy Cruze Premier


A learning experience is one of those things that says, "You know that thing you just did? Don't do that."

mercuic: Long live the tractor motor!

pipboxer
Posts: 9
Joined: 1 March 2012
Year and Model: 1998 v70 T
Location: colorado springs

Post by pipboxer »

It sounds like I'm a doof but when you say "vacuum tree" I dont know, but ill google it!!

I'm thinking weaker fuel pump with weak check valve (118000k mi.), I thought fpr but no fuel there in vacuum.
I think I can get a fuel pressure gauge from autozone or something and further diagnose.
I still have heater core, windshield and brake rotors, srs reset,abs light,ignition spins around 360 sometimes, now possibly fuel pump.WHEW , It gets real!! I think I got this girl off craigslist $1500 right before it was gonna go downhill!! Pcv was defibrillator. I falling in love with these cars. It seems if your struggling, your doing it wrong.
Your awesome community

pipboxer
Posts: 9
Joined: 1 March 2012
Year and Model: 1998 v70 T
Location: colorado springs

Post by pipboxer »

is this the vacuum tree and your pouring in the larger opening ?
Thanks for your patience ;)

http://www.fcpeuro.com/products/volvo-v ... 70-6842446

jblackburn
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Year and Model: 1998 S70 T5
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Post by jblackburn »

Yes, but the larger opening goes to the idle control valve and can't be unhooked with the car running.

Grab one of the smaller lines that comes off the tree - on a 1998, there's a yellow one that goes up to a white one-way valve and then goes into a valve at the radiator. Unplug that one and it will be fine to use. Make sure you plug it back into the valve after you are done.

Make sure you DON'T choke or stall the engine as the directions on the can say, or you risk hydrolocking it or bending a rod or something. I suck in a little bit at a time, let it recover, and then repeat until it takes up 1/3 of a can. Then shut the motor off and wait 10-15 minutes.

It's your choice if you feel uncomfortable using it in the intake manifold; many of us have done this and had no problems with it, but there are horror stories out there. Personally, I think they did something wrong like sucking it in too fast. Engines don't like things they can't compress (like water).

I've done it myself twice now, with good results in how the car ran afterwards both times.
'98 S70 T5
2016 Chevy Cruze Premier


A learning experience is one of those things that says, "You know that thing you just did? Don't do that."

mercuic: Long live the tractor motor!

pipboxer
Posts: 9
Joined: 1 March 2012
Year and Model: 1998 v70 T
Location: colorado springs

Post by pipboxer »

perfect explanation thank you so much, easy does it,now I'm not nervous hahaha

mrwillie
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Joined: 23 November 2011
Year and Model: 1994 855 base
Location: Raleigh,NC

Post by mrwillie »

jblackburn wrote:I had that happen even after I changed it.

I took the top hose off to the valve cover that snakes down through the intake manifold to the oil separator and poured 1/3 a can of Seafoam down it.

Then the 1/3 in the intake manifold and 1/3 in the gas tank as recommended.

Voila! Smoke gone, even on my 217K mile motor.
Ive done seafoam treatments on other cars, and even have an IV-type setup that I use to regulate the flow. Ive read from the MDS of seafoam that it contains a good solvent. Did u actually mean that you poured it down the tube that runs into the top of the oil trap? If I tried this in small amounts, w/ a hot engine and let it sit for an hour or so would it break enough oil down to start freeing up a clogged oil trap system? I noticed that running a shop vac on the same hose lessens the crankcase pressure for a few days.

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