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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

93 Cobra will not idle

  • Thread starter Thread starter Will86
  • Start date Start date Sep 22, 2009
W

Will86

New Member
Sep 22, 2009
1
0
0
Sep 22, 2009
#1
  • Sep 22, 2009
  • #1
Hey guys,

I have a 93 Mustang Cobra and just finished installing a bunch of mods including AFR Street 165cc heads, trick flow upper and lower intake manifolds, crane cam (part # TFS-51402000) 24lb venom injectors, and a BBK fuel rail with an Accufab adjustable regulator.

I was able to get the timing dialed in and break in the cam however I cannot get the engine to hold an idle. If I slowly back off the throttle the engine will idle rough around 900 then eventually die. If I rev the motor up and let the revs fall naturally the motor will instantly die. I pulled the some of the plugs and the motor looks like its running extremely lean.

I used to have a C&L 76mm mass air flow housing, however, it ran better when I swapped the stock housing back on the engine.

I originally thought my issue was vacuum related. I checked all lines and gasket surfaces over and was unable to find and sources of vacuum leak. I also had a master mechanic look at the car and he ruled out a vacuum leak. Even if the injectors were to small for this setup I doubt their duty cycle could be maxed out at idle. Has anyone else run into this issue or have any suggestions on how to remedy this problem? Thanks!
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Sep 22, 2009
#2
  • Sep 22, 2009
  • #2
You ran any codes yet?
 

86turbo

Member
Apr 8, 2006
183
0
17
Sep 24, 2009
#3
  • Sep 24, 2009
  • #3
your ecu. Doesn't it use a 19lb metered maf but is internally calibrated for use with 24's?? Using a dif meter would cause that thing to run all kinds of crazy.....no?

Drew
 
A

apstang50

New Member
Oct 12, 2009
6
0
0
W. Yarmouth, MA
Oct 19, 2009
#4
  • Oct 19, 2009
  • #4
X2 the MAF needs tobe calibrated to the injecters.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Oct 19, 2009
#5
  • Oct 19, 2009
  • #5
No factory Ford meter is calibrated to an Injector size.

The Transfer curve is different though.
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Oct 25, 2009
#6
  • Oct 25, 2009
  • #6
Will86 said:
I used to have a C&L 76mm mass air flow housing, however, it ran better when I swapped the stock housing back on the engine.
Click to expand...
Either use the stock Cobra MAF, or put some effort into the verifying the proper C&L MAF is being used.


The sensor used on the C&L housing is dependent on what ecu is being used.
A9L = F1ZF-*** part number
X3Z = F1SF-*** part number

Also,
The sample tube diameter depends on the ecu being used.


Visit the C&L calibration page for more info, or you can send me a pm, or post additional questions here.
Just be patient, as I don't have time to get on here as much as I used to

Good Luck,
jason
 
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