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Smoke in high RPMS

  • Thread starter Thread starter JamesB88
  • Start date Start date Apr 7, 2007
J

JamesB88

Member
May 29, 2004
228
0
16
North Kansas City
Apr 7, 2007
#1
  • Apr 7, 2007
  • #1
My 88 has started smoking pretty good when you take it up to about 4000rpms, it only does it if you stay up in the Rpms for awhile. It puffs alittle smoke when you start it at first but not much. Quess i need to do a compression check putting alittle oil in cylenders and see if it goes up any. Think it could be the heads or rings? Im getting ready to do a Heads and intake swap (car already has a E cam). But hate to put $1000 worth the parts on a junky bottom end. Its also getting oil into the upper intake, threw the tube on the valve cover, it smokes alittle out of it after its been runing for awhile, not a alot but its noticble if you remove the oil cap.
 
A

armyjon

New Member
Oct 29, 2006
29
0
0
Apr 7, 2007
#2
  • Apr 7, 2007
  • #2
sometimes your valve stem seals cause smoking by letting in oil at higher rpms
 
J

JamesB88

Member
May 29, 2004
228
0
16
North Kansas City
Apr 7, 2007
#3
  • Apr 7, 2007
  • #3
Thats what i was thinking the motor only has about 140psi compression. I quess that alright. Quess ill see what it runs like with my Roush 200 heads, cobra intake, and E cam.
 

_jb_

New Member
Mar 4, 2004
808
0
0
Michigan, Berrien County
Apr 8, 2007
#4
  • Apr 8, 2007
  • #4
Have someone follow you down the road and let off the gas, downshift a gear or two so the engine revs high and let the engine slow you down. If smoke starts to come out it's the valve seals. The vacuum will pull oil into the engine.
 
J

JamesB88

Member
May 29, 2004
228
0
16
North Kansas City
Apr 8, 2007
#5
  • Apr 8, 2007
  • #5
Ill have to try that, it does it when im on it, never paid attention when im letting off, only does it getting on the highway and if i drop it to 3rd on the highway.
 

_jb_

New Member
Mar 4, 2004
808
0
0
Michigan, Berrien County
Apr 8, 2007
#6
  • Apr 8, 2007
  • #6
It's the rings most likely then. How many miles are on it?
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Apr 9, 2007
#7
  • Apr 9, 2007
  • #7
S/D mustangs run a little ritch in the higher RPM's rather than mass air stangs. what colour is the smoke. Mine does the same but it's fuel not oil or coolant
 

Mr Grim

New Member
Dec 29, 2006
58
0
0
Apr 9, 2007
#8
  • Apr 9, 2007
  • #8
You mentioned that you are getting oil in the intake. Could be getting pulled in through the PCV valve if the basket is dirty, or missing. Not sure if it would pull in enough to cause it to smoke, but something else to look at. There have been a couple of posts around here lately about this issue.
Good luck,
-Grim
 
J

JamesB88

Member
May 29, 2004
228
0
16
North Kansas City
Apr 10, 2007
#9
  • Apr 10, 2007
  • #9
Its blowing smoke out of the oil cap when car is runing if you take the cap off, that line that runs from the valve cover to throttle body has smoke going threw. I was looking at it the other day at my parents and started reving it up and it was smoking from under the car, it turns out it is spraying oil out of the oil pan gasket, or rear main (i just changed it about 6k ago along with the clutch/tranny) But its getting on the headers and making it smoke pretty bad, there is alittle coming out of the exhuast. But i think it smoking out of valve cover is blow by, probly needs rebuilt anyways.
 

officer dick

New Member
Apr 10, 2007
26
0
0
NC
Apr 10, 2007
#10
  • Apr 10, 2007
  • #10
I'm having a similar problem with my 95 GT. However I'm getting puffs of smoke when I launch and shift at WOT. A quart of oil is lasting me about 300-800 miles depending on how I ride it. My initial thought is the valve seals, I'm hoping thats it. Any recommendations for an EFI 5.0?
 
J

JamesB88

Member
May 29, 2004
228
0
16
North Kansas City
Apr 10, 2007
#11
  • Apr 10, 2007
  • #11
Thats about how much oil i am using, but mines leaking it and blowing it by. Have you ran a compression test on your car? If its low, probly needs rings or head work. How many miles are on it? Stock motor?
 

officer dick

New Member
Apr 10, 2007
26
0
0
NC
Apr 10, 2007
#12
  • Apr 10, 2007
  • #12
It's got about 91k on it all stock except a K&N cold air. I'm going to run a compression check later this week then, I planed on replacing the gasket anyway while replacing the valve stem seals. Speaking of which, what size seals do I need to get?
 

ninety15.0

New Member
Mar 10, 2004
1,336
0
0
Apr 11, 2007
#13
  • Apr 11, 2007
  • #13
In terms of the seals spend the extra couple dollars for the "Viton" seals. They are a flouroelastomer with better sealing, temp range, and wear characteristics. Maybe 2 bucks a piece if i remember correctly.
 

officer dick

New Member
Apr 10, 2007
26
0
0
NC
Apr 11, 2007
#14
  • Apr 11, 2007
  • #14
Thanks for the tip, but there are two different sizes available @ summitracing, .500 and .530, which one should I get?
 

officer dick

New Member
Apr 10, 2007
26
0
0
NC
Apr 12, 2007
#15
  • Apr 12, 2007
  • #15
Also, let's say it is the piston rings, is there a quick and easy way to replace those?
 

Aryan15

Member
Sep 22, 2003
236
0
17
CA
Apr 12, 2007
#16
  • Apr 12, 2007
  • #16
It requires breaking into the bottom end to replace rings.
 
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