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Lots of Blue & Black Smoke? Running Rich?

  • Thread starter Thread starter SiK91LX
  • Start date Start date Sep 10, 2004
S

SiK91LX

New Member
Apr 23, 2003
78
0
0
SF, CA
Sep 10, 2004
#1
  • Sep 10, 2004
  • #1
I got :

New Motor (50K)
New T5 Tranny (45K)
FMS 3.73
Edelbrock Performer
AFR185 64CC
STOCK CAM (havent installed x404)
BBK Pullies
24lb Injectors
77MM Maf
BBK Fuel Pressure Regulator
STOCK FUEL PUMP (havent installed 190)
BBK Unequals Headers
BBK Offroad H pipe
Smog Pump Delete
A/C Delete
Ford Racing 2row Aluminum Radiator
Electric Fan
180thermostat
Hurst Short Shifter
King Cobra Clutch


:::::
Ok my fuel pressure is 40 and when i popp off the vaccum it jumps to 50PSI flat
:::::

So when normal cruising im running fine, no smoke nothing, but when i get on the gas all of a sudden theres blue/black smoke everywhere, when i had the old motor i didnt have this much smoke so had me wondering, i havent played with the fuel pressure yet, some are telling me to drop the fuel pressure to 33 and see what changes it brings..

Something to do with spark plug gapping?

Remember my fuel pressure is at 40PSI and when i take off the vaccum, it jumps to 50psi w/ stock fuel pump 24lb injectors
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Sep 10, 2004
#2
  • Sep 10, 2004
  • #2
check pcv valve?? and maybe a compression test.
 
S

SiK91LX

New Member
Apr 23, 2003
78
0
0
SF, CA
Sep 10, 2004
#3
  • Sep 10, 2004
  • #3
PCV Valve? What do you mean check it? check for dirt? or should i just replace it lol
 

ninety15.0

New Member
Mar 10, 2004
1,336
0
0
Sep 10, 2004
#4
  • Sep 10, 2004
  • #4
your FP is part of your problem. Im not totally sure about how much FP you should be running with all the mods you have but 50 is too much i think. either way, your FP isnt going to give u blue smoke thats oil. I would replace the PCV its like 3 bucks. the other thing is that 50k isnt exactly new in a built motor...i also think a compression check wouldnt be a bad idea. good luck man
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Sep 10, 2004
#5
  • Sep 10, 2004
  • #5
Sounds like way too much fuel with 50psi and 24's...

Rule of thumb, black smoke = too much fuel. Blue smoke = OIL (bad). White smoke = COOLANT (bad).
 
S

SiK91LX

New Member
Apr 23, 2003
78
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0
SF, CA
Sep 10, 2004
#6
  • Sep 10, 2004
  • #6
But people are also telling me that blue smoke is normal since i have no cats, no smog pump lol theres no white smoke at all and car runs gooodd - its a miture of blue and black smoke...
 
S

SiK91LX

New Member
Apr 23, 2003
78
0
0
SF, CA
Sep 10, 2004
#7
  • Sep 10, 2004
  • #7
so does anyone know what my fuel pressure should be?
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Sep 10, 2004
#8
  • Sep 10, 2004
  • #8
Pretty sure around 38psi.. i think thats with the vacuum off? Someone will confirm i'm sure...

Blue smoke means your burning oil, cats won't determine how much oil your car burns.
 

ninety15.0

New Member
Mar 10, 2004
1,336
0
0
Sep 10, 2004
#9
  • Sep 10, 2004
  • #9
well heres the thing. the stock FP is set at 38 psi with vac off. with my combo it likes to run best at 42 psi which is still a little high. since you have bigger injectors than me and dont have forced induction of any kind i would say that between 40-43 vac off is where u should be. the other thing is that not having cats has nothing to do with blue or black smoke. there are a ton of us on here without cats that dont blow blue or black smoke. black smoke is a clear sign of excess fuel, and blueish/gray smoke is oil. worn piston rings or poor valve seats can cause oil to blow through and come out the exhaust. thats why mavrick said BAD because it usually indicates a more serious problem. however you can blow oil when your PCV is clogged or not functioning. and seeing as the PCV is a 3 dollar part i would start there. also turn the FP down a little bit, it should actually make the car run a little stronger.
 
7

71vert-pga

New Member
Dec 18, 2003
145
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0
Bell Chasse, LA
Sep 10, 2004
#10
  • Sep 10, 2004
  • #10
SiK91LX said:
But people are also telling me that blue smoke is normal since i have no cats, no smog pump lol theres no white smoke at all and car runs gooodd - its a miture of blue and black smoke...
Click to expand...

No smoke is normal - PERIOD! Blue smoke is bad. A clean running engine is just that. Clean. It does not smoke.
 
S

SiK91LX

New Member
Apr 23, 2003
78
0
0
SF, CA
Sep 16, 2004
#11
  • Sep 16, 2004
  • #11
Ok i havent started up the car recently but the day i posted this message i raced a BONE STOCK 5.0 AUTO and i only pulled a car on him, he hung all the way from 2nd to 3rd and after 4th i started pulling.. He ran a 14.9 @ 97MPH - I ran a 14.1 on street tires with a 2.160ft

Im guessing it has to do with my fuel pressure - im gonna drop it down to 40with vaccum off and see how it does if not then im going to replace the spark plugs, PCV valve and see how it does...
 
S

SiK91LX

New Member
Apr 23, 2003
78
0
0
SF, CA
Sep 16, 2004
#12
  • Sep 16, 2004
  • #12
Oh also, recently we installed the Edelbrock Performer intake and IDLE has been rough, on 1st startup the car would idle at 500 and jump to 1300 and then drop back down to 400-500 and die - But after it has warmed up the idle is fine at 750.. Can this be also a part of the blac/blue smoke? Maybe vaccum leak causing some king of issue?
 
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