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Has this happened to anyone else?

  • Thread starter Thread starter cammed89lx
  • Start date Start date Mar 14, 2011
C

cammed89lx

New Member
Oct 25, 2010
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Mar 14, 2011
#1
  • Mar 14, 2011
  • #1
Hello, this started happening about a week ago. I would start my car, and drive it around for a little, park it, go do something for 10 minutes. then come back out and start it and nothing.. it will just turn over forever(15 seconds), so i feed it more gas(carbed) then keep turning over and it will eventually fire but idle at like 200 rpm,even while flooring it. then eventually after idling at 200 for like 5 seconds it will catch itself and idle normal. However if i drive it then go do something and it sits for more than an hour it will start up perfect. Is this a sign of my coil overheating or something. I just changed the plugs. Any ideas?? thank you
 

4rdnut

Member
Dec 14, 2010
188
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Mar 14, 2011
#2
  • Mar 14, 2011
  • #2
I thought you had a efi engine, i didn't read your carbed, you don't have a tfi module on the distributor, you would have one on the fenderwell like a duraspark module, it could still be the module though, disregard the pics.
 
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cammed89lx

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Oct 25, 2010
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Mar 14, 2011
#3
  • Mar 14, 2011
  • #3
Ok, so in my case, do i replace this, and mount it else where. What would you guys do. Is it expensive
 

Wildstringer

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Feb 20, 2011
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Mar 15, 2011
#4
  • Mar 15, 2011
  • #4
If you car is carbed, do you still have the module mounted on the distributor? The module usually causes a no start not a hard start. It sounds like a carb issue. Maybe a choke acting up in some way. Maybe the whole carb needs a rebuild.
 
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cammed89lx

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Oct 25, 2010
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Mar 15, 2011
#5
  • Mar 15, 2011
  • #5
hmm. if thats the case im confused, because the carb only has about 6000 milse on it
 

jrichker

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Mar 15, 2011
#6
  • Mar 15, 2011
  • #6
You should not have the original TFI equipped distributor on a carbed car. There is no way to properly advance the timing. The EFI computer uses information from the computer sensors to advance the timing.

If you bought the car and it was a carb conversion, you were taken advantage of. I hope you stole it because if you didn't you got robbed.

If you did the EFI to carb conversion, you are lacking in vast amounts of knowledge on how carbed cars operate.

Check for flooding. The extended crank is because the engine is either flooded or can't get enough fuel and air. Holding the throttle to the floor without pumping it clears the excess fuel out of the engine. The flooding usually a result of damaged power valve, incorrect float level or excessive fuel pressure. The fuel pressure at the carb should be about 4-6 PSI.

Do not use an EFI in tank fuel pump with a carb. You will never get the pressure/flow regulated properly. Either go full EFI or use a tank/fuel pump/fuel lines out of an 84 or earlier Stang. Fabricating your own setup is possible but there are some snags to overcome.

Do not attempt to leave the EFI computer in place in an attempt to control either the electric fuel pump or ignition. Doing so qualifies you for the “Road Kill Mechanics Award”.

If you try to use your current tank, you will need to pull the fuel pump out and fabricate a pickup tube & strainer sock to replace the fuel pump. Or you can have a sump fabricated and welded onto you existing tank. Many welding shops will not weld fuel tanks because of the dangers involved if the tank isn't purged properly.

You will need an external electric fuel pump unless you change the timing cover for one with the mechanical fuel pump mount on it. Rip all the EFI wiring out, and the computer controlled fuel pump won't work. You will need to add a relay & switch and wire in the existing inertia switch for an external low pressure electric fuel pump. Do not try to wire the fuel pump without the relay. The 15-20 amps the pump pulls will overload the circuit. This will take power away from other items on the same circuit or cause the fuse or fuse link to blow.




While you are at the electrical part, you'll need a Durspark or similar ignition system. The 85 Mustang GT 5 speed has a suitable Duraspark distributor with a steel gear compatible with the roller camshaft. The EFI ignition depends on the EFI sensors to advance the spark. Rip out the TPS and MAP/Baro sensors and the computer will have no idea of the proper ignition timing for best performance. Running a fixed timing setting is only for test purposes or for a race track only car. Don't try it on the street: the results will not be nearly as good as a properly setup Durspark or equal. Crane makes a really nice distributor for non-EFI applications. . See Crane Cams | Automotive Home Page for more information. Cost is about $400, which makes the 85 Mustang reman units look really appealing.
 
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