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  • 1965 - 1973 Classic Mustangs -General/Talk-

69 Mach1 Promblems... Need Help

  • Thread starter Thread starter MachMy1
  • Start date Start date Sep 1, 2013

MachMy1

Member
Sep 1, 2013
2
2
14
Florida
Sep 1, 2013
#1
  • Sep 1, 2013
  • #1
I've had this car for quite some time and it just never ran right. My dad owned this car and left it to me when he died. The problems started after he was gone. See I wont list any names or labels to who, but there were several people in charge of the will that did not want me to have this car. They held it from me until they legally had to give it up. So between my dad owning it and that person holding it, there was sabotage done to the car.

Since I have taken possession, the car has had the electrical worked on twice, I've had professionals look at it and tell me nothing is wrong with the car, I've had the Alternator tested, battery tested and switched out.. I'm getting so emotionally upset about it, because this was something I valued the most when my dad died...

The Problem


The car starts, it drives for about 20 minutes and then sputters out and wont restart until its cooled off. Some times it wont start for a day or two. The battery doesn't die and it gets hot. I've solved the over heating issue but it still stalls out. When it starts to stall it sputters only when coming to a slow, at a stop light or hitting the brake to stop completely. In drive it sputters out, and in reverse but when its in park it will run until the gas is gone. The alternator charges the battery but you can only start it back up when everything has had a chance to cool off.

Work Done

Change thermostat, change relay for the starter. When tampering around i discovered when the lights are switched on and the brake held in while in drive it sputters out a lot faster. Is it an electrical issue? Is it the starter? Brake booster? Seal leak? Please, I need some help.....
 

horse sence

15 Year Member
Nov 29, 1999
12,178
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Wile Coyote's stunt double
Sep 1, 2013
#2
  • Sep 1, 2013
  • #2
may be somthing in the gass tank .or the sock filter on the suction tube is plugged
you may have a blown out brake booster causing an large vaccume leak when brakes are pushed ,do the brakes feel like power?
 

MachMy1

Member
Sep 1, 2013
2
2
14
Florida
Sep 1, 2013
#3
  • Sep 1, 2013
  • #3
Thought of the gas and dropped the tank... Cleaned it out and did new 93 oct, What was odd was it didn't have a fuel filter so I installed one and it seemed to idle better but it didn't solve the stalling. I was told by someone else that it may be the Break booster... The breaks it takes a lot it seems for it to stop. I have to push hard.
 

horse sence

15 Year Member
Nov 29, 1999
12,178
7,998
233
Wile Coyote's stunt double
Sep 1, 2013
#4
  • Sep 1, 2013
  • #4
sounds like the booster is blown out . start it and let it run for a minute .turn it off then pull the check valve,where the hose attaches , out of the booster and see if it hisses .if not the booster is probably bad. it should hold vacuum .though the valve its self could also be bad.that you can test with a vacuum gauge .you could also suck on the valve it will only work one way if good.
 

horse sence

15 Year Member
Nov 29, 1999
12,178
7,998
233
Wile Coyote's stunt double
Sep 1, 2013
#5
  • Sep 1, 2013
  • #5
one more way to tell if it is the booster or the valve is to plug the hose to the valve and see if it keeps running
 

no1hedberg

Member
Aug 5, 2013
33
1
9
Sep 9, 2013
#6
  • Sep 9, 2013
  • #6
Sounds kinda like a vapor lock situation to me. What kinda condition is the fuel pump and carburetor in? Next time it won't start you might want to pull off the air cleaner and look down in the throat of the carb and pump the throttle. You are looking for a stream of fuel spraying toward the butterflies in the bottom of the carb.
 
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