1991 Mustang LX Smell Fuel in Exhaust, Bogging down

J

James Sims

New Member

Mar 13, 2004

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0

May 13, 2008

#1

• May 13, 2008

• #1

1991 Mustang Smell Fuel in Exhaust, Bogging down Code 91 HELP!!

-NEW WATER PUMP
-TIMEING CHAIN
-TFS TRACK HEAT UPPER AND LOWER WITH STAGE 1 PORT
-GT40 HEADS
-SCORPION 1.7 ROCKERS
-24LB INJECTORS
-ADJUSTABLE FUEL REGULATOR
-New Fuel pump 255
-F CAM
-Z RATED 93 COBRA 5 SPEED
-93 COBRA COMPUTER
-70 MM MASS AIR
-THROTTLE BODY
-NEW MOTOR MOUNTS
-BASSANI HEADERS
-BASSANI X PIPE WITH CATS
-NEW STAGE 2 CLUTCH
W/ STEEDA ADJUSTABLE CLUTCH CABLE AND CLUTCH QUADRANT THAT HAD

These are all the mods are the car, I do have a tweecer too that I havnt used just yet.....
I can smell fuel in the exhaust and it falls on its face at 2500rpm I have tried everything need some help! Timing has been checked it sitting at 14.5 or so! help please

 

ls1beater4eva

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May 13, 2005

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mooresville

May 13, 2008

#2

• May 13, 2008

• #2

whats your fp set at? and when u say falls on its face at 2500 is it just like laying over or spitting and popping ? what kind of maf are you running? what kidn of balancer are you useing

 

J

James Sims

New Member

Mar 13, 2004

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May 13, 2008

#3

• May 13, 2008

• #3

fp set at 39psi and its spitting and popping detonation, my maf is stock from a 93 cobra, what do you mean by balancer? James

 

J

James Sims

New Member

Mar 13, 2004

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0

May 15, 2008

#4

• May 15, 2008

• #4

ran the codes last nite

I ran the codes last nite iam getting a 91 which is oxygen sensor problem, fuel pressure out of specified range or injectors out of balance! hmmmm

 

ram360

Founding Member

Oct 19, 2002

2,162

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59

Pennsylvania

May 15, 2008

#5

• May 15, 2008

• #5

Code 41 or 91 - O2 indicates system lean. Look for a vacuum leak or failing O2 sensor.

I also pull 91 new 02 sensors and I know for a fact the car is hella' rich. You happen to run long tube headers?

 

backfocus

Member

Sep 3, 2004

254

3

18

Little Rock, AR

May 15, 2008

#6

• May 15, 2008

• #6

Need more info on the computer and the Mass air. The computer is for sure a cobra unit? What is the Mass Air, is it a Cobra unit as well? Just asking since the cobra computer compensates for the injectors in the computer and not the Mass air.

 

2000xp8

SN Certified Technician

Aug 8, 2003

8,037

1,625

194

NJ

May 15, 2008

#7

• May 15, 2008

• #7

It's probably the o2 sensors.
They are a common problem.

I'd also ditch the cobra computer and meter, in exchange for a stock computer and PMAS meter. Although i doubt they are the problem, but they are certainly a restriction.

 

97vertstang

Member

Aug 17, 2005

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6

fontana ca

May 16, 2008

#8

• May 16, 2008

• #8

ram360 said:

Code 41 or 91 - O2 indicates system lean. Look for a vacuum leak or failing O2 sensor.

I also pull 91 new 02 sensors and I know for a fact the car is hella' rich. You happen to run long tube headers?

Click to expand...

im having a similar problem, and it happened after i installed my long tube headers. how does it all tie together and whats the problem???

 

ram360

Founding Member

Oct 19, 2002

2,162

1

59

Pennsylvania

May 16, 2008

#9

• May 16, 2008

• #9

97vertstang said:

im having a similar problem, and it happened after i installed my long tube headers. how does it all tie together and whats the problem???

Click to expand...

the 02 sensors are furuther down and they don't heat up. It's telling the computer it's lean and it's adding more fuel that I don't need My 02's are brand new and no vacuum leaks. Keep giving me code 91. I know for a fact the car is not lean whatsoever....in fact it's so rich it's to the point the exhaust burns my eyes. I have a tuner and pull %12 fuel out a idle just to compensate but its' more of a band aid than anything else at this point. I've yet to have someone tell me how to solve the issue...

 

ram360

Founding Member

Oct 19, 2002

2,162

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59

Pennsylvania

May 16, 2008

#10

• May 16, 2008

• #10

http://forums.stangnet.com/showthread.php?t=569946

 

J

James Sims

New Member

Mar 13, 2004

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0

May 17, 2008

#11

• May 17, 2008

• #11

bad injectors

I changed out the injectors last nite! it fixed the problem!!! bad injectors! simple enough! james