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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

1991 5.0 slow starting

  • Thread starter Thread starter bad_decision
  • Start date Start date Jan 8, 2023
B

bad_decision

Member
Aug 14, 2020
10
2
13
Houston, TX
Jan 8, 2023
#1
  • Jan 8, 2023
  • #1
I am trying to pinpoint the reason for my fox body's slow starting condition. It cranks every time, but is a slow crank and sounds like one of those cars where you're crossing your fingers hoping it fires up. I've done the below wiring upgrades mainly to support the new alternator, but was hoping it would help with the slow start condition:

  • SVE 130A alt.
  • Alt power wire to battery positive - 4 gauge.
  • Battery negative to engine block - 4 gauge.
  • Battery positive to starter solenoid - 4 gauge.
  • Body ground beside battery to a/c mounting bracket - 4 gauge. I don't know if this is the stock location or if it's even a good ground. This replaced a small frayed wire that was in place when I got the car.
  • Starter solenoid to starter - 4 gauge.
I have not tested the battery but it is only 2 years old. Replaced by previous owner when he put it up for sale. Spark plugs are fresh and clean, and the car has a new-ish ignition coil and PDI billet distributor. I have not messed with the starter or starter solenoid.

Car holds 14.3-14.4v at idle with all accessories on.

Even though it starts reliably, I don't want it to sound old and tired. Any tips on what I can test or troubleshoot to track this down?
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
28,112
10,729
213
polk county florida
Jan 8, 2023
#2
  • Jan 8, 2023
  • #2
Voltage drop test on the battery to starter, slow crank conditions heat things up like wires and starter.
alternator would have nothing to do with slow cranking, only battery, wires or starter.
this has been my experience.
 
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