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running rich

  • Thread starter Thread starter sdrt
  • Start date Start date Sep 20, 2009
S

sdrt

New Member
Mar 1, 2009
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Sep 20, 2009
#1
  • Sep 20, 2009
  • #1
my car is running extremely rich when it warms up. i have brand new o2 sensors and is giving me no codes. it will go through a tank of fuel in about 120 miles!! could it be my fuel pressure is to high? i don't have a gauge hooked up yet what should it be? thanks.
 

liljoe07

5 Year Member
Feb 18, 2009
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Cartersville,Ga
Sep 20, 2009
#2
  • Sep 20, 2009
  • #2
Little more info on the Setup would help.

But 120 miles to a tank is crap. If its running that rich, it will have codes. Most of the Time.

Did you do both KOEO and KOER codes?
 
S

sdrt

New Member
Mar 1, 2009
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Sep 20, 2009
#3
  • Sep 20, 2009
  • #3
sorry should have explained. it's a 93 lx bbk equal length,3 inch flowmaster exhaust 75mm throttle body stock injectors,pulley's smog delete,aod tranny,4.10 rear,stock manifold. when it's warm from a light you can put it on the wood and it's a pig!!.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
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Cartersville,Ga
Sep 20, 2009
#4
  • Sep 20, 2009
  • #4
You should have codes. We need the Codes.

If you are getting absolutely no flashes, then somethings wrong.

Few things to check.

Are the 02s actually getting power?
Is the 02 signal ground hooked up on the back of the heads or intake?

Again, need codes...LOL
 
B

BlueChevelle

New Member
Apr 3, 2009
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Sep 21, 2009
#5
  • Sep 21, 2009
  • #5
By chance did you pull the tank down? I changed my gas lines and it was running crazy rich (>60psi). The return hose had been crimped when i put the tank back up.
 
S

sdrt

New Member
Mar 1, 2009
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Sep 21, 2009
#6
  • Sep 21, 2009
  • #6
i did'nt do anything with the tank. i haven't put the adjustable regulator and pressure gauge on yet.what pressure is right?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
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Cartersville,Ga
Sep 21, 2009
#7
  • Sep 21, 2009
  • #7
40 Psi with vac line off.
 

jrichker

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Sep 21, 2009
#8
  • Sep 21, 2009
  • #8
Dumping The computer diagnostic codes on 86-95 Mustangs

Revised 19-May-2009 to update drawing for dumping the codes on 86-88 Mustangs with no check engine light.

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

See Troublcodes.net Trouble Codes OBD & OBD2 Trouble Codes and Technical info & Tool Store. By BAT Auto Technical





If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.
 

dcurtis

10 Year Member
Jan 19, 2006
688
7
39
Sep 21, 2009
#9
  • Sep 21, 2009
  • #9
Are you running the 75mm tb on the stock intake, or what intake are you running.
 
S

sdrt

New Member
Mar 1, 2009
19
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0
Sep 22, 2009
#10
  • Sep 22, 2009
  • #10
yes it is the stock intake with the 75mm throttle body and the kid i bought it from say's it's an e-cam but i cannot confirm that.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Sep 22, 2009
#11
  • Sep 22, 2009
  • #11
Still waiting on the Codes from the ECM
 
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