Help with starting issue

Id see if you have power to the solenoid on the fender with a test light when trying to start it. That would tell you if the circuit is good all the way from the key to the solenoid. Pull the little 90 degree boot off and have someone try to start the car and use a test light and see if you are getting power.

There is a switch on the clutch arm assy. that should engage when the pedal is pushed down. It allows the starter to work only when the clutch is disengaged. It prevents you from starting the car in gear and running into something, so do not permanently bypass it. It sounds like your switch is not making contact or is unplugged etc. It is the first place I'd look if you are still a skinny kid and can get under the dash. If not, get someone else to squeeze under there.

Mine cuts out all the time. Think they are like $100. and definitely not fun to get too.....only reason I live with it for now. Think you can adjust them at the switch right where that little rod with the odd cap is, but not sure.

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If you are 5 10 and weigh 265 like I do save your self a whole bunch of trouble and pull the drivers seat out before you try to wedge yourself up under the dash

No Crank checklist for 5.0 Mustangs

Revised 05-Oct-2010 to update Fluke references.

No crank, slow crank and stuck starter solenoid problems have the same root causes – low battery voltage and poor connections. For that reason, they are grouped together.
Use the same initial group of tests to find the root cause of both no crank and stuck solenoid problems.

Since some of the tests will bypass the safety interlocks, make sure that the car is in neutral and the parking brake is set. Becoming a pancake isn’t part of the repair process…

1.) Will the car start if it is jumped? Then clean battery terminals and check battery for low charge and dead cells. A good battery will measure 12-13 volts at full charge with the ignition switch in the Run position but without the engine running.
A voltmeter placed across the battery terminals should show a minimum of 9.5-10 volts when the ignition switch is turned to the Start position and the starter engages or tries to engage. Less than this will result in a clicking solenoid, or slow cranking (if it cranks at all) or a starter solenoid that sticks and welds the contacts together.

Most auto parts stores will check your battery for free. It does not have to be installed in the car to have it checked; you can carry it with you to the auto parts store.

The battery posts and inside of the battery post terminals should be scraped clean with a knife or battery post cleaner tool. This little trick will fix a surprising number of no start problems.

The clamp on with 2 bolts battery terminal ends are a known problem causer. Any place you see green on a copper wire is corrosion. Corrosion gets in the clamped joint and works its way up the wire under the insulation. Corroded connections do not conduct electricity well. Avoid them like the plague...

If the starter solenoid welds the contacts, then the starter will attempt to run anytime there is power in the battery. The cables and solenoid will get very hot, and may even start smoking. The temporary fix for a welded starter solenoid is to disconnect the battery and smack the back of the solenoid housing a sharp blow with a hammer. This may cause the contacts to unstick and work normally for a while.

A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the voltage drop across a connection while trying to start the car: more than .5 volts across a connection indicates a problem. The voltage drop tests need to be done while cranking the engine. It's the current flowing through a connection or wire that causes the voltage drop.

See http://assets.fluke.com/appnotes/automotive/beatbook.pdf for help for help troubleshooting voltage drops across connections and components. .



2.) Check the battery to engine block ground down near the oil filter, and the ground behind the engine to the firewall. All grounds should be clean and shiny. Use some sandpaper to clean them up.

3.) Jump the big terminals on the starter solenoid next to the battery with a screwdriver - watch out for the sparks! If the engine cranks, the starter and power wiring is good. The starter relay is also known as a starter solenoid.

The rest of the tech note only concerns no crank problems. If your problem was a stuck solenoid, go back to step 1.

4.) Then pull the small push on connector (small red/blue wire) off the starter solenoid (Looks like it is stuck on a screw). Then jump between the screw and the terminal that is connected to the battery. If it cranks, the relay is good and your problem is in the rest of the circuit.

5.) Remember to check the ignition switch, neutral safety switch on auto trans and the clutch safety switch on manual trans cars. If they are good, then you have wiring problems.

Typical start circuit...
Diagram courtesy of Tmoss & Stang&2birds



6.) Pull the starter and take it to AutoZone or Pep Boys and have them test it. Starter fails test, then replace it. If you got this far, the starter is probably bad.


Starter solenoid wiring for 86-91 Mustang



Starter solenoid wiring 92-93 Mustang or earlier Mustang with upgraded high torque mini starter.


Electrical checks for the switches and starter solenoid

Remove the small red/blue wire from the starter solenoid. Use a screwdriver to bridge the connection from the battery positive connection on the starter solenoid to the small screw where the red/blue wire was connected. The starter should crank the engine. If it does not, the starter solenoid is defective or the battery lacks sufficient charge to crank the engine.

If the starter does crank the engine, the problem is in the clutch safety circuit (5 speed) or Neutral Sense Switch (auto trans) or ignition switch.


See the Typical start circuit diagram above for wiring information for troubleshooting.

You will need a voltmeter or test lamp for the rest of the checks. Connect one lead of the voltmeter or test lamp to ground. The other lead will connect to the item under test.
Look for 12 volts on the white/pink wire when the ignition switch is turned to the Start position. Check the ignition switch first.
No 12 volts, replace the ignition switch.

The next step will require you to push the clutch pedal to the floor (5 speed) or put the transmission in neutral (auto trans) while the ignition switch is turned to the Start position.
Good 12 volts, check the clutch safety switch (5 speed) or Neutral Sense Switch (auto trans) for good 12 volts on both sides of the switches. No 12 volts on both sides of the switch and the switches are defective or out of adjustment. Check the wiring for bad connections while you are at it.

louieb said:

I have noticed when i press the clutch down, sometimes i need to repeat that step to get the starter to engage.

now i can only push start. does this have anything to do with ignition switch, or is this starter issue?

Click to expand...

There is a safety switch which prevents the starter from working
without depressing the clutch. I removed mine completely. It's a matter of just taking the switch out of the circuit [ two wires shorted together]. I have been behind the wheel for many years.I always start the car in neutral anyway.

squekster said:

There is a safety switch which prevents the starter from working
without depressing the clutch. I removed mine completely. It's a matter of just taking the switch out of the circuit [ two wires shorted together]. I have been behind the wheel for many years.I always start the car in neutral anyway.

Click to expand...

Be super careful of doing this. I have seen people un knowingly start the car in gear and you can imagine what happens. I remember seeing a girl get ran over by a Fiero in high school that had the neutral safety jumped out. It's a safety switch for a reason. I'm do preaching, lol.... Sorry

I broke the side mirror on an old work truck that did not come with the switch. Smacked on the garage door track. I was in a hurry and was used to an automatic. I fixed it before telling the boss and he liked the bigger mirror anyway. That was lucky.