Check the Battery Voltage post to post.
If you have 12.7 Volts more or less your battery is fully charged.
1.
With car in neutral (car won't start but would jump forward on starter power if in some gear), jumper the purple wire with Positive Battery post.
2. Now if you have a No Start/no engine turn over (car will not start but engine should turn over), either the purple wire connection to starter is failing (from the point of your jumper) or you have a sticky Solenoid, burnt Solenoid points, bad solenoid Coil, or starter bound up on flywheel.
3.
This is assuming you have a good connection to the starter from the positive battery post (in other words you are getting power to the Starter main coil (only interrupted by a poor Solenoid Points or inoperable Solenoid) .
4. If you hear a click (
Solenoid activating and plunger moving forward) you have only Solenoid ponts to deal with as shown below or
your connection from battery to starter main circuit is failing or starter coils or bearings or something else internal to starter (even starter gear bound up on flywheel as suggested in item #3 above.
I would suggest that those starter failures would be rare in this case since all this happened only when you changed batteries. That coincidence would be REMOTE.
5.
Now if car starts (actually it will not start with the jumper but definitely the starter will turn the engine over) with the purple wire jumper. It becomes obvious you have something in the ignition circuit eating up voltage to give you only 11.5 volts in purple wire (as measured before you jumped the purple wire).
Inspection, Testing and Reconditioning the Valley, Starter, and Coils
Starter Solenoid Contacts.
I had a NO START condition on a 90' and after I towed it for a start....got home and it fired right up.
I would have liked to hot wire the starter (purple wire) when that happens to see if it is the starter or starter ground circuit. Or check that purple wire for 12+ volts when I turn the switch to start. I lean toward ground circuit or sticky starter solenoid. Another indication would be if when you turn the ignition key to start do the lights dim for example indicating a current draw to the starter solenoid/starter.
If the solenoid does not move (no clicking indicating the Starter Solenoid did not move) as in my case then a sticky Solenoid or Solenoid Ground Connection. If the Solenoid clicked/moved...then bad Solenoid contacts or bad connection Battery cable (Positive) to starter/battery or bad ground (Negative) engine to battery.
I Installed a relay in the start circuit of the 90' identical to what I have on the 91' which basically provides direct power from battery to starter Solenoid when relay is activated. This is one of those intermittent issues and does sound like poor electrical connections in either the Starter Negative Connections or Starter Positive Connections.
Starter Relay, Wiring Harness, Battery, and Plugs Tricks
The Starter Solenoid is shown in the left photo with slight burnt contacts in right photo.
The Solenoid contacts in left photo were wire brushed clean in right photo.
Complete Starter Disassembly.
Photo provided by others.
