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COBRA ECU X3Z problems on my fox

  • Thread starter Thread starter mustang863
  • Start date Start date Aug 20, 2010

mustang863

Member
May 30, 2009
112
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Aug 20, 2010
#1
  • Aug 20, 2010
  • #1
built 347
trick flow tw 170 heads
1.73 roller rockers
24lb
x3z ecu and mafs
just tune the car runs good but when i shift its a 5 speed like 1 to 2 not driveing the car the idel drops sometimes dies if i shift it back and forth i can kill the car any ideas no runing problems it just bugs me
 

jrichker

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#2
  • Aug 20, 2010
  • #2
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.
 

mustang863

Member
May 30, 2009
112
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Sep 15, 2010
#3
  • Sep 15, 2010
  • #3
how come when i jump it i dont get any engine light flashing and now im geting a engine light after runing?
 

Mustang5L5

That is…until I whipped out my Bissell
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#4
  • Sep 15, 2010
  • #4
What year is this car? Did you do a MAF conversion? Is the VSS installed?
 

vristang

15 Year Member
Mar 31, 2005
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Sep 15, 2010
#5
  • Sep 15, 2010
  • #5
mustang863 said:
built 347
trick flow tw 170 heads
1.73 roller rockers
24lb
x3z ecu and mafs
Click to expand...
You used both the 93 cobra MAF housing & the 93 cobra MAF sensor, correct?

mustang863 said:
just tune the car runs good but when i shift its a 5 speed like 1 to 2 not driveing the car the idel drops sometimes dies if i shift it back and forth i can kill the car any ideas no runing problems it just bugs me
Click to expand...
I'm sorry, but I have no idea what any of this means...
 
L

Lawbreaker5.0

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Feb 20, 2009
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Texas
Sep 15, 2010
#6
  • Sep 15, 2010
  • #6
I assume it's an auto and when he shifts it's not smooth it pauses like a 5 speed. :idunno:
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
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Massachusetts
Sep 15, 2010
#7
  • Sep 15, 2010
  • #7
That's why we need more info
 

mustang863

Member
May 30, 2009
112
9
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Sep 17, 2010
#8
  • Sep 17, 2010
  • #8
1992 lx 5.0 5-speed

yep did the match maf and ecu
 

mustang863

Member
May 30, 2009
112
9
16
Apr 18, 2011
#9
  • Apr 18, 2011
  • #9
found the problem last tuned on a moates chip sorry for the late update lol
 

jrichker

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#10
  • Apr 19, 2011
  • #10
mustang863 said:
how come when i jump it i dont get any engine light flashing and now im geting a engine light after runing?
Click to expand...

No code 11 (two flashes when the computer dumps the codes)? The 11 code is computer passed its internal self test.

If you don't get an 11, you have computer or wiring problems.

Please check and repost.
 
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