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11/09/2018 11:29 AM  #1

Friends 289 Coupe SPUTTER!?!?!

Ok I will give as many details as I can by memory and knowledge!

289 ALL ORIGINAL and never rebuilt Motor!  Approx. 150,000m.....
New Plugs, Cap, Rotor, Condensor and points.
New Wires and Coil
New Fuel Pump
New Alternator and 4bbl AL intake with Holley Economaster Carb
New Vac lines everywhere (snuff the carb engine dies within 2-3 sconds)
Idle is at 650 give or take....Vac reads 17-18 (bounces)

before intake job car had a Sputter!  mild like sputter, intermittent but Now, the SPUTTER is pronounced and much more Violent....I tried to notice a pattern and can not.....When the sputter Occurs, you feel it throughout the Car and it Feels like a MOMENTARY "shut-off"   Sounds radical but its the best way I can describe it!  almost as if fuel instantly Stopped, 10mil/sec re-flowed....or like spark quit, then reshot!
ONLY AT IDLE OR LOWER RPM (max900-1200) and Mostly when In N or Park!?

While Driving, hesitation or performance issue, STRONG at higher rpm.....

ANYTHING????  im lost


11/09/2018 11:55 AM  #2

Re: Friends 289 Coupe SPUTTER!?!?!

Some items to check:
Carburetor float level - verify correct level
Idle mixture screws - make small adjustments to see if anything changes.
Idle passages in carb may need cleaning.  You can try spraying cleaner into passages but best bet may be to rebuild it.
Check and verify ignition timing is correct, at idle and watch to verify it advances when RPM is raised.
Check the dwell of the distributor, w/150k miles the cam that the points ride on in the distributor may be worn and need to be replaced.  Note that this usually causes missing at higher RPM, but would be good to verify.
I doubt the fuel pump is a problem, they tend to either work, or not.

65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.

11/09/2018 12:59 PM  #3

Re: Friends 289 Coupe SPUTTER!?!?!

1 st   float level
2 nd  move from pointer to electronic ( just the basic)
3 rd  check carb and refurbish
4 rt    check air leaks from intake
5 th  refer on  spark plug state (maybe are drawning in gasoline )

Seems the same footprints on the snow ...  you are doing the same path and my car  simpthoms ended when i redone carb and make it lean  , set a proper timing , moved to pertonix pick ups  .
How many cfm ?


11/09/2018 2:00 PM  #4

Re: Friends 289 Coupe SPUTTER!?!?!

carb was brand new in the box 3 weeks ago.  450cfm rating, double pumper. 

keep in mind folks this only occurs violently in Neutral and Park, and much more subtle in gear at a stop......

higher rpm performance is perfect.....

     Thread Starter

11/09/2018 4:01 PM  #5

Re: Friends 289 Coupe SPUTTER!?!?!

You didn’t mention it is a automatic. Check vac line to modulator and modulator itself. I had that same problem on a newer Ford and it was the vac line to the trans.

"anyone that stops learning is old, whether at twenty or eighty"Henry Ford

11/09/2018 5:56 PM  #6

Re: Friends 289 Coupe SPUTTER!?!?!

Look at the coil.......I had one where fire was jumping across ...intermittently.
My money is on something in ignition.

"Get busy liv'in............or get busy die'n!!"

Board footera

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