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Engine running rich

  • Thread starter Thread starter Begizzle
  • Start date Start date Apr 6, 2008

Begizzle

Member
Jun 19, 2005
49
0
7
Apr 6, 2008
#1
  • Apr 6, 2008
  • #1
I have a 93 lx. stock bottom end h/c/i with supporting mods. I am running base fuel psi at 40 with 30 lb injectors and calibrated maf. It has all new sensors including o2 sensors. Base timing at 16. The car starts up and runs great from a cold start. It will idle smoothly at 900 rpms. Once the engine is up to operating temps it starts smoking badly. The smoke is like a bluish tinted smoke but it definately smells like fuel and it burns your eyes. The car still idles smoothly and runs great. The shortblock was just rebuilt and has 0 miles. Motor has 45 psi oil pressure at idle.

What could be the problem? I was thinking o2 sensors since it only happens once the engine is warm. Also, I have a holley fuel psi regulator and the pressure drops to zero once the car is shut off. Is that normal?
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Apr 15, 2008
#2
  • Apr 15, 2008
  • #2
could it be IAT inlet air temp? Almost sound like it is going into choke mode. If it was rich from get go I would suspect ECT sensor. Engine coolant temp. Still could be an issue.
 

tb9050lx

Member
Mar 7, 2004
155
3
19
ct
Apr 16, 2008
#3
  • Apr 16, 2008
  • #3
Begizzle said:
I have a 93 lx. stock bottom end h/c/i with supporting mods. I am running base fuel psi at 40 with 30 lb injectors and calibrated maf. It has all new sensors including o2 sensors. Base timing at 16. The car starts up and runs great from a cold start. It will idle smoothly at 900 rpms. Once the engine is up to operating temps it starts smoking badly. The smoke is like a bluish tinted smoke but it definately smells like fuel and it burns your eyes. The car still idles smoothly and runs great. The shortblock was just rebuilt and has 0 miles. Motor has 45 psi oil pressure at idle.

What could be the problem? I was thinking o2 sensors since it only happens once the engine is warm. Also, I have a holley fuel psi regulator and the pressure drops to zero once the car is shut off. Is that normal?
Click to expand...

i think your injecters are too big for this setup 24 lbs might be a tad better!!!
 
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