5.0 fox blowing smoke help

02vertable

Member

Aug 7, 2018

50

3

8

Queen creek Arizona

Dec 5, 2018

#1

• Dec 5, 2018

• #1

I've got a 1991 5.0, with about 104 thousand miles on it. I recently noticed that after I sit at a light for a minute and then start going again, it blows blue smoke out the back. Once I'm moving I dont really see any. Obviously its burning oil. Are my rings worn out? I put a new PCV valve in it but I couldn't get that mesh filter out from underneath it, could that be it? There is also some evidence that my upper to lower intake manifold gasket is leaking, could that be it? Anybody know if theres anything else I should be looking at and how to fix it?

 

fredfifty

5 Year Member

Nov 23, 2011

318

57

59

SF Bay Area

Dec 5, 2018

#2

• Dec 5, 2018

• #2

use a wood screw taped to the end of a long screwdriver and use that to "grab" the mesh screen..worked for me

 

Reactions: Rdub6 and General karthief

General karthief

wonder how much it would cost to ship you a pair

5 Year Member

Aug 25, 2016

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polk county florida

Dec 5, 2018

#3

• Dec 5, 2018

• #3

Are you seeing and smoke from the dip stick tube or oil fill tube with the engine running?
do a compression check.
you may just need valve seals, has the car been sitting a long time?

 

Mustang5L5

That is…until I whipped out my Bissell

Mod Dude

Feb 18, 2001

43,216

17,899

224

Massachusetts

Dec 5, 2018

#4

• Dec 5, 2018

• #4

Usually I think worn rings blow blue at WOT and leaking valve seals blow blue at lower speed or after engine sits

 

Alley Oop

Member

Mar 29, 2017

71

12

18

West Coast of Canada

Dec 5, 2018

#5

• Dec 5, 2018

• #5

I've used the something like a wood screw (wine cork screw) at the end of a screwdriver, it works.

 

D

ddtmoto

New Member

Dec 7, 2012

2

0

1

Dec 8, 2018

#6

• Dec 8, 2018

• #6

Yup, you're going to need a compression, and probably a leak down test. Step by step testing to determine your engine's overall health. Most likely Piston blow-by or seals. Start with the easiest stuff. Not that it's going to be easy....
If you're not in a hurry to tear things down, add a load of AT-205 to a fresh change of a heavier High Mileage weight engine oil....and see what spring time brings...?

 

02vertable

Member

Aug 7, 2018

50

3

8

Queen creek Arizona

Dec 10, 2018

#7

• Dec 10, 2018

• #7

General karthief said:

Are you seeing and smoke from the dip stick tube or oil fill tube with the engine running?
do a compression check.
you may just need valve seals, has the car been sitting a long time?

Click to expand...

Theres no smoke coming from there. And as far as I know, the car never sat very long. I did see some evidence of dry rotting on the fittings for the vacume lines under the intake, and theres evidence that my upper and lower intake manifold gaskets are leaking, could that cause it? The thing just blows a little blue smoke after stoplights sometimes.

 

General karthief

wonder how much it would cost to ship you a pair

5 Year Member

Aug 25, 2016

27,868

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polk county florida

Dec 10, 2018

#8

• Dec 10, 2018

• #8

The blue puff of smoke after idling for a time is usually valve seals, a leaking intake gasket could be too, check vacuum lines and the pcv valve and screen too. Valve seals, sometimes called umbrella seals, would be my guess.