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Electrical need help no start with 5 volt reference

  • Thread starter Thread starter 86mstang
  • Start date Start date Apr 29, 2022
8

86mstang

New Member
Apr 29, 2022
5
0
1
west virginia
Apr 29, 2022
#1
  • Apr 29, 2022
  • #1
i have an 86 gt and done a mass air conversion. the car has sit for several years and i tried to put the car back on the road last year but it would idle for a while and shut off and not restart until the next day then the same issue. i got to checking and i had no 5 volt reference from the computer so a friend gave me a computer and with it the car would not start but would try and that was it. i put the old computer back in and the car would run so i opened up the computer and someone had run a wire in place of the 5 volt trace and the wire came loose so i soldered it and now the car will not run with that ecm either. i am at a loss i have tried 3 mass air flow sensors unhooked the throttle sensor, mass air and egr but still have not been able to get the car to start it will try but that is all it does. i also put a new distributor in it but still no start with 5 volts. i am thinking about disconecting the 5 volt wire in the computer and see if it will start again that way. thanks
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Apr 29, 2022
#2
  • Apr 29, 2022
  • #2
Does the fuel pump prime or continue running.
 
8

86mstang

New Member
Apr 29, 2022
5
0
1
west virginia
Apr 29, 2022
#3
  • Apr 29, 2022
  • #3
The fuel pump primes.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,866
10,540
203
polk county florida
Apr 29, 2022
#4
  • Apr 29, 2022
  • #4
Does it start with starting fluid?
 
8

86mstang

New Member
Apr 29, 2022
5
0
1
west virginia
Apr 29, 2022
#5
  • Apr 29, 2022
  • #5
Have not tried that yet will try tomorrow
 
8

86mstang

New Member
Apr 29, 2022
5
0
1
west virginia
May 2, 2022
#6
  • May 2, 2022
  • #6
it will start off starting fluid so now either fuel pump is not pumping or injectors not firing. i do not have a valve i can find to check fuel pressure. thanks
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,866
10,540
203
polk county florida
May 2, 2022
#7
  • May 2, 2022
  • #7
You should be able to hear the pump run for a few seconds when the key is turned to the on position.
 
8

86mstang

New Member
Apr 29, 2022
5
0
1
west virginia
May 2, 2022
#8
  • May 2, 2022
  • #8
Yes the pump runs for a few seconds and shuts off. Will change filter and go from there. May be a defective pump.
 
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