This guy was telling me that you can remove the tubing running from the pcv valve to the intake and plug it at the intake. Then install an air filter in line to the PCV valve. He said that this keeps the PCV valve from robbing air from the intake and is supposed to add a few horses. Has anyone ever done this or heard of doing this? Just wanted to know.

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JJ
97 F150 Lariat 4x2 4.6l V8 Wht/Blue Flowmaster 40s Cat back system, K&N Filter, DeeZee Bugshield and Vent Visors

 

I think the PCV robs nothing from the intake. It is supposed to recycle some of the exhaust gas back through the intake to burn more of the junk out of the exhaust so you end up with a cleaner burning engine.

You may also have trouble passing a smog test with that type of mod including it is illegal to modify/remove smog devices.

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97 F-150, 2WD, Reg Cab,Flareside,Dk Toreador Red, 4.6, 3.55 LS, EGR Bug Deflector, ******* Bed Cover, Bed Liner, XL Full Length Running Boards, Air Aid Kit, Gibson Single Out Cat Back, Superchips, TransGo Shift Kit, Hellwig Rear Sway Bar, Hellwig 2500# Overload Springs

 

I agree with most of what Indyfan said, you aren't going to gain any performance by plugging the PCV valve and you will lose crankcase ventilation and fumes will get out to the atmosphere. But I think the main reason for PCV is to prevent the blowby and oil fumes from making a sludgy, slimey mess in your oil pan.

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Danny
'98 F-150 Std., RC, SB, 4x2, 4.2L, 5-sp, 3.08, AC, speed control, rear slider
with Syntec engine oil, MTL trans fluid, Edelbrock shocks, 50 Series Flowmaster, K&N with airbox mod, electric radiator fan

 

Thanks guys. I was just wondering, you know always looking for something.

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JJ
97 F150 Lariat 4x2 4.6l V8 Wht/Blue Flowmaster 40s Cat back system, K&N Filter, DeeZee Bugshield and Vent Visors

 

HI!... PCV- stands for POLLUTION CONTROL VALVE.

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NEAL [ the horsepower freak ] NEWMAN
'99' F-150 XLT SPORT, oxford white, reg cab shortbox stepside,5.4, auto, 3.55L.S, captain's chairs, bedliner, GTS carbon fiber headlight covers, **** CEPECK clear halogen driving lights, GTS slotted tailight covers (painted oxford white), FORD locking lug nuts, tinted windows,true duel exhaust with 2.5 inch mandrel bent pipes and FLOWMASTER 3 chamber mufflers with 3' tailpipes exiting before the rear wheel like the LIGHTNING, HELLWIG rear stabalizer bar, AUTOMETER guage pod and tranny temp guage, custom fabricated air intake trac and huge K/N filter, TPS mod, BELLTECH 2-inch rear drop, SUPERCHIP (truck won't start,"DAM"!!, soon to be installed 4.10 gears.

 

PCV stands for Positive Crankcase Ventilation (which should make the rest of this explanation redundant, but I'll do it anyway). During the compression stroke some of the air/fuel mixture gets by the rings (called blowby), it ends up in the crankcase where it mixes with fumes from the hot oil. To avoid building up pressure in the crankcase and blowing seals these fumes are sucked out by the intake vacuum through the PCV valve and re-burned, this also avoids releasing these fumes into the atmosphere. The PCV valve only allows air to flow in one direction, so it won't "rob" anything from the intake side.
I hope this helps, please feel free to correct me where I'm wrong.

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1999 Lariat Super Cab, S.B. 5.4L, 3.55 LS
and everything but the leaky slider window.
Bright red w/ gold 2-tone
Mods: Duraliner bedliner, Bugflector II
& a leeetle chrome tip on the exhaust.



[This message has been edited by Indyfan (edited 08-19-1999).]

 

Sorry Neal:
"PCV" is an abbreviation for "positive crankcase ventilation". I certainly would NOT advise bypassing, or otherwise disconnecting it. A fellow I knew [not very well] in the Army years ago tried plugging the PCV in his Camaro, because his buddies had told him it was worth several hp. Several days later, I saw him in the base auto-hobby shop. One of the valve covers had "ballooned" a bit,apparently because the blowby gases had nowhere to go [he didn't see any hp increase, either].

 

Since there is litte vacuum in the intake manifold at WOT the PCV valve is not operating anyway.
PCV only operates when there is a partial vacuum in the intake manifold. (most of twe time)
Aside from pollution control it also helps the oil last longer and reduces sludge for the reason that 4DThunder gives below.

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99 XLT 5.4l reg cab
4 wheel disc/ABS
5 star larait style wheels
Toreador red 2tone
3.55 gears
255/70/16 OWL
Delta toolbox
Eclipse 5340 cd player
Memphis ARCS50 component speakers (excellent sound)
Sherwood amp
subwoofer coming soon
More mods as funds become avalible.

[This message has been edited by 54regcab (edited 08-22-1999).]

 

HI!... JERRY I don't know what they call a PCV where you are from , but here in CANADA it is known as a POLLUTION CONTROL VALVE. I used to be a mechanic and my brother is still one and we both learned in school that a PCV is a pollution control valve. Either way what we call it, it still does the same function.

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NEAL [ the horsepower freak ] NEWMAN
'99' F-150 XLT SPORT, oxford white, reg cab shortbox stepside,5.4, auto, 3.55L.S, captain's chairs, bedliner, GTS carbon fiber headlight covers, **** CEPECK clear halogen driving lights, GTS slotted tailight covers (painted oxford white), FORD locking lug nuts, tinted windows,true duel exhaust with 2.5 inch mandrel bent pipes and FLOWMASTER 3 chamber mufflers with 3' tailpipes exiting before the rear wheel like the LIGHTNING, HELLWIG rear stabalizer bar, AUTOMETER guage pod and tranny temp guage, custom fabricated air intake trac and huge K/N filter, TPS mod, BELLTECH 2-inch rear drop, SUPERCHIP (truck won't start,"DAM"!!, soon to be installed 4.10 gears.

 

When pistons move up and down they also move air/gases with them. When they move up it is a compression stroke, when they move down they also move air/gases only this time they would be compressing they oil pan/crank area so this area has to be vented, hence "positive crank ventilation" or PCV. These valves have been on engines since before any greenpeace demonstrator was born.Correction:They started installing them in the mid-60's, before that they had breathers on the valve cover.

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Red 99.5 Lightning,#0975,Born 5/6/99...Adopted 5/27/99 SuperChip



[This message has been edited by 4D THNDR (edited 09-11-1999).]

 

JJHarris - and others
Say guys, we may not like the things that are done to the motors in our trucks but one thing is for sure. The manufacturers have a full time staff who design these systems all day long and I have to believe they know more about it than I do. Disconnecting one of these systems such as the PCV (Positive Crankcase Ventilation) will probably cause one or more of the other systems in the truck not to function as designed. There are many systems that must work together to get the end result. If you throw it out of balance, you're just asking for a problem. I too wish we could go back to the days when there was just one fan belt going around the alternator and you could actually see the valve covers.

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Black '97, SC with 4.6, 3.55 gears, automatic, 2-4 Belltech drop kit, SnugTop fiberglass lid, 3 chamber Flowmaster muffler, billet bumper grill, fog lights, American Racing 17x8 wheels with 275-60 Goodyear Eagle GT II tires.

 

I know for a fact when this thing gets plugged up naturaly (from not changing it regularly or cleaning it) that oil leaks from everywhere. So it must not be a good idea to plug it deliberately.

 

As a Canuck, I've heard it called both. From what I know about engines, having torn down a few, I wouldn't mess with the PCV valve. I'd rather burn those gases than send them up into the atmosphere for my kids to breath.

Better plan is to work the intake (keep swapping the filter or add K&N or similar) and SuperChip it if you want more speed. And use high-test gas and add 5 lbs to your tires. Helluva difference.

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1998 XL SC short-box 4.2 5-speed 3.55LS, Pacific Green, A/C, factory box liner, factory dark tinted rear glass (like the XLT), cassette, carpet, Canadian XLS package (split bench, chrome wheels, side mouldings, box light, tailgate lock), sill guards, Windstar (driver's) wiper blade (the one with the air scoop). Oh ya: snazzy Tweetie Bird floor mats.

New 2000 F-150 on order, same as the current one except black and XLT. Great trucks!