Slow cranking


15 Year Member
Jul 13, 2003
Tucson AZ
When i start the car it seems to crank over slowly? Could this be due to a slowly going out starter maybe drawing to many ohms? Or a ground? I have L/T's with a mini starter. I also have a 150 amp inline fuse and it blew it, and now i'm on my 3 rd kill switch as for i relocated the battery to the trunk. Could someone post up pics of all the engine compartment grounds and how many there is? I think there is what 1 on each side of the engine to the mounts one on the fire wall and then what ? Also please say where they connect to on the car. I have a 93 5.0 coupe. peace

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New Member
Feb 8, 2006
Aberdeen, WA
on mine there is a ground that connects to almost directly under the timing cover, same thing happened to my dads truck a few weeks ago after we put on headers, the ground might be bad..take a set of jumped cables and stick one black clamp to the battery, and the other black clamp to a good ground such as the block, that might help, also does it do it worse when it's hot?



"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
The LT's probably are not a cause since it happens cold.

Jrichker has a nifty post with all the engine grounds listed. For quick diagnostics, putting a jumper cable on the engine and running the other leg to the frame makes for a nice motor ground. If it helps, you have narrowed down the issue.

I couldn't tell if you still have some sort of issue with fuses or switches frying. If so, that could be wiping out your battery. Or the battery itself is the issue (it wont deep cycle), or battery connections or cables are at fault.

Good luck.


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In Remembrance. Thank you for your contributions
Mar 10, 2000
Dublin GA
Grounds are important to any electrical system, and especially to

1.) The main power ground is from engine block to battery: it is
the power ground for the starter & alternator.

2.) The secondary power ground is between the back of the
intake manifold and the driver's side firewall. It is often missing or
loose. It supplies ground for the alternator, A/C compressor
clutch and other electrical accessories such as the gauges.
Any car that has a 3G or high output current alternator needs
a 4 gauge ground wire running from the block to the chassis
ground where the battery pigtail ground connects.

The 3G has a 130 amp capacity, so you wire the power side
with 4 gauge wire. It stands to reason that the ground side
handles just a much current, so it needs to be 4 gauge too.

The picture shows the common ground point for the battery & alternator

Picture courtesy timewarped1972

3.) The computer has its own dedicated power ground that
comes off the ground pigtail on the battery ground wire. Due to
it's proximity to the battery, it may become corroded by acid
fumes from the battery. It is a black cylinder about 2 1/2" long
by 1" diameter with a black/lt green wire. You'll find it up next to
the starter solenoid where the wire goes into the wiring harness

4.) All the sensors have a common separate ground. This
includes the TPS, ACT, EGE, BAP, & VSS sensors.

5.) The O2 sensor heaters have their own ground (HEGO ground)
coming from the computer. This is different and separate from
the O2 sensor ground. It is an orange wire with a ring terminal
on it. It is located in the fuel injector wiring harness and comes out
under the throttle body. It gets connected to a manifold or bolt on
back of the cylinder head.

6.) The TFI module has 2 grounds: one for the foil shield around
the wires and another for the module itself. The TFI module
ground terminates inside the computer.

7.) The computer takes the shield ground for the TFI module and
runs it from pin 20 to the chassis near the computer.

8.) The computer's main power ground (the one that comes from
the battery ground wire) uses pins 40 & 60 for all the things it
controls internally.

Check battery, terminal connections, ground, starter relay switch (also known as solenoid)
and starter in that order. The clamp on with 2 bolts battery terminal ends are a know
problem causer.

A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the
voltage drop across a connection: more than .5 volts across a connection indicates a problem.
See for help

for help troubleshooting voltage drops across grounds

Extra grounds are like the reserve parachute for a sky diver.
If the main one fails, there is always your reserve.

The best plan is to have all the grounds meet at one central spot
and connect together there. That eliminates any voltage drops
from grounds connected at different places. A voltage drop
between the computer ground and the alternator power ground will effectively
reduce the voltage available to the computer by the amount of the drop.


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