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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Wet Plugs

  • Thread starter Thread starter Lnarranger
  • Start date Start date Jul 9, 2017
  • Tags Tags
    black wet spark plugs

I have a rebuilt '87 5.0 that puts out black smoke. plugs wet and black within 1 minute

  • crack in intake

    Votes: 0 0.0%
  • wrong injectors

    Votes: 2 100.0%

  • Total voters
    2
L

Lnarranger

New Member
Jul 9, 2017
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0
1
Jul 9, 2017
#1
  • Jul 9, 2017
  • #1
I have a rebuilt '87 mustang 5.0. The plugs will be black and wet within 1 minute, then the engine runs ruff and black smoke. Idle bypass, egr, and coil are all new. ????
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
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Jul 9, 2017
#2
  • Jul 9, 2017
  • #2
Sounds like its running pig rich. What color are the injectors ?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,176
17,878
224
Massachusetts
Jul 9, 2017
#3
  • Jul 9, 2017
  • #3
Two things.

Specs on what is done to the engine

Have you run the engine codes? If not, can you do this and report back what you get?
 
L

Lnarranger

New Member
Jul 9, 2017
6
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1
Jul 9, 2017
#4
  • Jul 9, 2017
  • #4
90sickfox said:
Sounds like its running pig rich. What color are the injectors ?
Click to expand...
90sickfox said:
Sounds like its running pig rich. What color are the injectors ?
Click to expand...
orange
 
L

Lnarranger

New Member
Jul 9, 2017
6
0
1
Jul 9, 2017
#5
  • Jul 9, 2017
  • #5
Lnarranger said:
I have a rebuilt '87 mustang 5.0. The plugs will be black and wet within 1 minute, then the engine runs ruff and black smoke. Idle bypass, egr, and coil are all new. ????
Click to expand...
Engine rebuilt to factory specs for 87 mustang 5.0. Getting code 98 and 54
 
L

Lnarranger

New Member
Jul 9, 2017
6
0
1
Jul 9, 2017
#6
  • Jul 9, 2017
  • #6
Mustang5L5 said:
Two things.

Specs on what is done to the engine

Have you run the engine codes? If not, can you do this and report back what you get?
Click to expand...
Engine codes are 98 and 54. The injectors are Accel 150819. Engine was rebuilt to factory specs for 87 mustang 5.0
 

90sickfox

Wasn't a pretty sight...and I've got big hands
SN Certified Technician
Mar 2, 2015
6,945
5,816
213
Jul 9, 2017
#7
  • Jul 9, 2017
  • #7
Is the timing set correctly ? Jrichker may be able to chime in with a timing check list....or look it up on your own.

The orange tops are the correct ones. Has the car been converted to 5 speed...or computer swapped ? Just asking because the O2 sensor harnesses are different.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,176
17,878
224
Massachusetts
Jul 9, 2017
#8
  • Jul 9, 2017
  • #8
Code 54 is ACT circuit open.

Code 98 is a hard fault.
 
L

Lnarranger

New Member
Jul 9, 2017
6
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1
Jul 9, 2017
#9
  • Jul 9, 2017
  • #9
90sickfox said:
Is the timing set correctly ? Jrichker may be able to chime in with a timing check list....or look it up on your own.

The orange tops are the correct ones. Has the car been converted to 5 speed...or computer swapped ? Just asking because the O2 sensor harnesses are different.
Click to expand...

The engine and ECU are from an 87 mustang. They are now in a '77 Bronco with a c-4 automatic. I am about to run a vacuum and compression test. What would be the process to check the ECU? With all of the sensors being new could it be weak or giving false commands?
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,844
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polk county florida
Jul 9, 2017
#10
  • Jul 9, 2017
  • #10
Do you have the plug to run the codes?
If you swapped the bronco computer for the 87 it may be pinned different, were they the same numbers? Speed density? Mas air?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,176
17,878
224
Massachusetts
Jul 10, 2017
#11
  • Jul 10, 2017
  • #11
What engine harness are you using?
 
Reactions: 90sickfox
L

Lnarranger

New Member
Jul 9, 2017
6
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Jul 16, 2017
#12
  • Jul 16, 2017
  • #12
Every sensor on the engine was replaced with new. Installed an external ground wire on the ECM. Went back to basics, brought #1 piston up, marked where the rotor was pointing, picked the distributor up and placed the cap #1 spot right in front of it. Runs like a new one. I appreciate all of you who tried to help. Thank you.
 
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