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Engine running rich

  • Thread starter Thread starter 87DIB5.0
  • Start date Start date Dec 13, 2019
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87DIB5.0

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Jun 9, 2018
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Dec 13, 2019
#1
  • Dec 13, 2019
  • #1
I have an 87 that has been switched to mass air. Its running rich and i cant find out why. I have pulled codes and comes back code 11 which i understand is system ok. It idles fine and runs fine. I have checked the mass air sensor, 02 sensor, TPS sensor, IAC sensor, and the coolant temp sensor and all read good. The fuel pressure regulator is set at about 38psi without the vacuum line connected. Any help will be greatly appreciated.
 
Last edited: Dec 13, 2019

General karthief

wonder how much it would cost to ship you a pair
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polk county florida
Dec 13, 2019
#2
  • Dec 13, 2019
  • #2
What maf and sensor? Are they matched to you injectors? What computer being used? How old are the O2 sensors?
Oh, and are your tires inflated properly?
 
8

87DIB5.0

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Jun 9, 2018
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Dec 13, 2019
#3
  • Dec 13, 2019
  • #3
It is a ford maf sensor that is matched to the 19lb injectors. the computer is an A9L. And the 02 sensors are probably a year old.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,926
10,572
203
polk county florida
Dec 13, 2019
#4
  • Dec 13, 2019
  • #4
What tells you it is running rich?
 
8

87DIB5.0

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Jun 9, 2018
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Dec 13, 2019
#5
  • Dec 13, 2019
  • #5
The fuel smell is so strong it burns your eyes if you sit stand next to it. also the spark plugs.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,926
10,572
203
polk county florida
Dec 13, 2019
#6
  • Dec 13, 2019
  • #6
Codes?
 
8

87DIB5.0

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Jun 9, 2018
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Dec 13, 2019
#7
  • Dec 13, 2019
  • #7
no codes, came back code 11 which i understand is system ok?
 

Blown88GT

Founding Member
Nov 13, 1999
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Palm Beach Gardens, FL
Dec 13, 2019
#8
  • Dec 13, 2019
  • #8
87DIB5.0 said:
It is a ford maf sensor that is matched to the 19lb injectors. the computer is an A9L. And the 02 sensors are probably a year old.
Click to expand...
The sensor doesn't do the match, the housing does. It could be the housing is not for 19lb. If you need one, I have 2 or 3 of the 55mm matched to 19lb. You can have one for the shipping cost. Just swap to your sensor.
 
Reactions: General karthief
D

Deleted member 215073

Dec 13, 2019
#9
  • Dec 13, 2019
  • #9
Are your catalytic converters still there and working?
 
8

87DIB5.0

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Dec 13, 2019
#10
  • Dec 13, 2019
  • #10
how do I determine if the housing is matched? I have no cats, bbk shorty headers to an x-pipe and dumped after Flowmaster 40series mufflers.
 
D

Deleted member 215073

Dec 13, 2019
#11
  • Dec 13, 2019
  • #11
Is it a stock MAF sensor and housing?
 

Olivethefet

I will own your nuts! LOL
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May 17, 2018
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Dec 13, 2019
#12
  • Dec 13, 2019
  • #12
Did this just start after you swapped it to mass air?
 
8

87DIB5.0

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Jun 9, 2018
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Dec 13, 2019
#13
  • Dec 13, 2019
  • #13
JMGlasgow said:
Is it a stock MAF sensor and housing?
Click to expand...
I’m not sure.
 
8

87DIB5.0

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Dec 13, 2019
#14
  • Dec 13, 2019
  • #14
Olivethefet said:
Did this just start after you swapped it to mass air?
Click to expand...
It was already done when I bought the car. But it has always run a little rich.
 
D

Deleted member 215073

Dec 13, 2019
#15
  • Dec 13, 2019
  • #15
Pictures of the MAF sensor and housing would help. There are numbers on the sensor that may help identify it.
 
8

87DIB5.0

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Dec 13, 2019
#16
  • Dec 13, 2019
  • #16
 
8

87DIB5.0

Member
Jun 9, 2018
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Dec 13, 2019
#17
  • Dec 13, 2019
  • #17
I’ve been reading that this is for a cobra, but the cobras come with 24lb injectors so it can’t be calibrated for my 19.
 
D

Deleted member 215073

Dec 13, 2019
#18
  • Dec 13, 2019
  • #18
Looks like a stock housing with the correct sensor.

O2 sensors in good shape?
 
8

87DIB5.0

Member
Jun 9, 2018
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Houston
Dec 13, 2019
#19
  • Dec 13, 2019
  • #19
It looks good. How can I test it? I’ve pulled it off while running and the car runs real rough so I know the computer is getting some reading from it.
 
D

Deleted member 215073

Dec 13, 2019
#20
  • Dec 13, 2019
  • #20
Not having cats is going to cause more fuel smell in the exhaust. You could try cleaning the MAF sensor, and the oxygen sensors may not be working very well if they're old.

Do you still have a functioning carbon canister?
 
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