will not hold idle, runs too lean
09-21-2009, 04:22 PM
#1
Thread Starter
Join Date: Sep 2009
Location: VA
Posts: 3
will not hold idle, runs too lean
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!
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!
09-22-2009, 07:04 AM
#8
Thread Starter
Join Date: Sep 2009
Location: VA
Posts: 3
09-22-2009, 12:31 PM
#10
6th Gear Member
Join Date: Nov 2006
Location: Spfld, MA
Posts: 9,240