Intermittent Starting Problem

nj2251

Registered User
My 1990 Super Coupe (35th Ann, automatic) only starts normally on first start up in the morning. The rest of the day, I must turn the ignition switch to Start position for 5-25 times before the engine starts. Today, after many failed attempts to start it (about 50 times), I finally had to get a screwdriver from my trunk and cross-bridge the solenoid relay and the engine started immediately. I brought the car straight home, parked, shut it off and tried to restart the engine. Nothing; not even a click. Tried to restart the car periodically with the key for the next 3 hours and it wouldn't start, but it started immediately with the key after sitting more than 3 hours. As a final test, I turned off the engine again and tried to restart; Nothing!! What can this be?
 
Can be the multi-wire ignition switch that resides on the steering column, right side, inside the dash.

Remove the two-piece surround bezel where the steering wheel meets the dash (3 philips head screws from below) and check it out...see if it is opening up when you turn the key...it shouldn't.

Duralast Ignition Switch LS514

Search here for tips on swapping it out. You will need a security Torx to do the job,
 
Could also be the starter solonoid that you jumped sticking( not closing) after getting warm from under hood heat which is why it work's 1st start when its cold or after letting cool off a extended amount of time.
 
Follow red/blu tracer wire with a test light, from starter solenoid to anti theft module in trunk. I've jumper wired an anti theft bypass on the red/blu wires before. The ignition switch can also be tested back at the anti theft module red/blu. The P/W goes from 12V with brake applied, to ground with key at start, and brake applied.
 

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The diagram on the left is misleading, as the starter interrupt relay is internal to the anti theft module. I just made a simple diagram. 1st, I would check for 12V on the Red/Blu wire at the starter relay. if ok, Check for corrosion at the starter relay mounting, ( for good ground). If not getting 12V at the starter relay, go to the anti theft module and check the white/pink wires at connector for 12V, with the ignition switch at start. If ok, check the red/blu wires for 12V with ign switch to start, and brake applied. Should have 12V. Check connectors for corrosion. Also the neutral start switch is between the ignition switch, and the anti theft relay.
 

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Thank you guys for all of your responses with possible causes and cures for my starting issues. This morning I started the car as usual and turned it back off almost immediately to determine if the starting problem is heat-dependent. The engine did not restart until I turned the ignition to Start eleven times. I really appreciate all of your input, but since I'm just a shade tree guy, I'm not savvy, trained and skilled enough to try your suggestions. I suppose I'll go back to the Ford dealer techs to take a look. I've had this same problem occasionally for 20 years and each time I take it to Ford, they change one part that resolves the problem for a year or two. The different parts historically have been the negative cable, stator, solenoid relay, positive cable, starter, and removed entire alarm system. Wonder what part they'll change this time that will last another year. I'll update you. Thanks again for all your help and happy holidays.
 
My 90 SC does the click, and no crank sometimes. The anti theft starter circuits have been jumped for years, and the starter solenoid, and connector have been replaced. Rarely doesn't crank. I would fine a good independent shop, or technician, rather than a dealer. Ask car savvy friends, and check yelp, and google, etc.
 
The ignition switch I mentioned is known for causing grief - If it has seen 20 years service, I'd bet even money on it being an issue.

All it takes to at least check it is 3 Phillips head screws, and removal of the two-piece trim. Once you can lay eyes on it, try turning the key and see if the switch is trying to come open.

If it is, then $20 and labor and done.

I've found the dealers aren't usually keen on seeing a SC roll in.

Whatever you do, try your best to not let someone fire the parts cannon at it ;)
 
KMT, this procedure looks simple enough. However, I've found out over the last 32 years that sometimes the simplest jobs turn into a nightmare. Nevertheless, tomorrow I will remove the trim piece and look at the multi-wire ignition switch before and during turning of the key. If the switch opens at all, I'll buy a new Duralast Ignition Switch and possibly a security torx from Autozone. Thanks a lot for the tip.
 
Possibly the NSBU switch? Next time it acts up, move it from Park to Neutral
& see if any difference or try wiggling shifter while holding key in start, just a thought.
 
Where is the NSBU located , just installed air e-vap and heater core, I hear a little click under the hood but no crank , is this the cable from the auto shifter to steering column ?
 
If you can hear the starter relay clicking under the hood, then everything up to that point
(ign & safety switch's & associated harness's) are good. Your issue is with the relay, starter, battery
supply to the relay or grounds.

The cable is for the shifter interlock-cant move shifter out of park when key tumbler in lock
 
Check the trigger wire on the starter, it's the small wire with spade terminal. If lose it will just click, tighten up by squeezing the female connection with pliers and reattach.
 
Sorry for the delayed response, but I want to thank everyone for their input regarding my intermittent starting problem. As it turned out, it appears that KMT was correct about the ignition switch. After examining and changing the ignition switch, I have not had any problem starting the car for the last two weeks. Starts every time I turn the key. Thanks again KMT and happy holidays to all.
 
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