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Topic: Lets play help me figure out what's with my ignition system (Read 1865 times) previous topic - next topic

Lets play help me figure out what's with my ignition system

Ok the 95 T-bird is driving me nuts:mad:

Lets start with a story.

Last night I was driving to my parents house are the car was running fine. I pulled up infront of their house the car just shut off. It wouldn't start back up. It had fuel but no spark. I went in and ate dinner and went back out about 1/2 hour later to check the car. It fired right up. I drove it home and figured I'd take it to AZ today to get it scanned for codes. I drove it to AZ today with no problems.They hooked it up and it didn't throw any codes. On the way home two blocks from my house it died again. I waited 1/2 hour and like magic it started right up again. Drove it home and shut it off. I could start it right up and did so 3 times in a row. I figured that the TFI module was dying and I went out and bought a new one (Motorcraft). I got home about 1/2 hour later and decided to check to see if the car would fire before I put the new module in. It wouldn't. I put the new TFI in and it still wouldn't fire. I had to go to work so I didn't mess with it for about 4.5 hours. I brought my dad with me so I could check for spark and the  thing fired :hick:


Sooooo here's where I found something interesting. After it started tonight I was playing with the ignition switch (you know the part where you put the key in:hick: ) and found something interesting.

1. If you turn the switch and pull on the key between *off* and *run* the heater blower motor comes on for second :wtf:

2. If you jimmy the key between *off* and *run* you can pull the key out and start the car with no key:hick: and it will run.

So I'm wondering if my problems could be traced to a bad ignition switch. Could it over heat and cause all these problems?



HELP! HELP! lol;)
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Lets play help me figure out what's with my ignition system

Reply #1
You don't put the key in an ignition switch, you put it in a lock cylinder, which then activates the switch. The switch could very well be your problem. Don't know if Ford still used the flaming switches in '95, but if they did you should be covered under a recall.
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1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Lets play help me figure out what's with my ignition system

Reply #2
I'm just shooting in the dark here:hick:

The switch isn't smoking or anything. My best guess it something is getting hot and shuting off after the car has run for a few minutes.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Lets play help me figure out what's with my ignition system

Reply #3
yep bad ign switch......see the same problem in just about every ford i've owned. welcome to the band wagon of broken ignition swithches.

Lets play help me figure out what's with my ignition system

Reply #4
Is there any way to check if it's the ignition switch before I go out and buy one? Well besides pulling it out and seeing if it looks like shiznit :hick:
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Lets play help me figure out what's with my ignition system

Reply #5
The key and tumbler and the switch are two different things.  I'm sure there is a way to check the switch itself but i'd just recommend changing it.

You'd probably need to pull it to check it anyway.
84 TC 302 -5.0L/t5/7.5 locking rear and a 3.45 gear, Edelbrock Intake, Aluminum Heads, Edlebrock 65mm Throttlebody, Edlebrock Cam, 24lb injectors & MAS Air Sensor calibrated via chip,  BBK headers, Catback H pipe, Magnaflow lers :evilgrin:
:pics-stfu:

 Project Thread with pics

Lets play help me figure out what's with my ignition system

Reply #6
So I pulled the harness off the ignition switch and the switch looked fine. No burn marks, melted plastic, or gooey stuff. So I'm guessing I can eliminate the switch as the problem. I had it idle in my driveway for 25 minutes and it wouldn't stall. I shut it off and then checked under the distributer cap. Everything looked ok. I then went to start it back up and it wouldn't start (tried it 3 times). I went into the garage to grab a screwdriver to check for spark and ran back out. Before I checked for spark I tried to start it again and the  thing started on the first try :mad: . I couldn't make it stall again. The only way I can make the  thing stall is to drive it, which is not a very good idea incase I get stuck somewhere and it stalls or doesn't start:mad:
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Lets play help me figure out what's with my ignition system

Reply #7
Lou, I would probably changed the ignition switch anyway. It might look fine on the outside, but you never know what it might look like inside.  Good luck

John


86' T/C 4.6L DOHC
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Lets play help me figure out what's with my ignition system

Reply #8
Well I verified no spark :hick:

So far I have replaced: cap, rotor, coil, and TFI (all Motorcraft stuff). I replaced the cap, rotor, and coil today. I purposely drove the car to the parts store to *warm it up* (the parts store is 7 blocks from my house) to pick up the parts. It stalled right after I started it outside the parts store but fired right back up. I drove it home changed the stuff and no start. So I checked for spark at the # 4 plug: no spark. Checked for spark from the coil wire: no spark. I waited 20 minutes and tried again. The car started (I then knew that I put the stuff on right:hick: ). So something is getting hot and shuting off. At this point it has to be the ignition switch right? What the hell else could it be?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Lets play help me figure out what's with my ignition system

Reply #9
sounds like there's a broken wire somewhere. Had a E-100 that would just die whenever unfortunately found the problem when the wiring harness started on fire. I would start at the ignition and work from there. also had a car with a broken ground problem. that one was a bear to find.
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***** Project "EVOLUTION" 1987 Cougar LS  & 1985 Cougar Convertible *****
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5.0 HO 306 roller block, machined GT-40P heads, Wiseco dished forged pistons, Eagle forged floating I-beam connecting rods, Lunati pushrods, ARP bolts, Scorpion aluminum 1.6 rockers, Comp Cams Magnum 266HR, Explorer intake, 65mm TB, MAF Conversion, 19# injectors, Ford Racing stainless P-headers, 2-1/2" cat-less exhaust w/ Flowtech Afterburner lers , SC AOD with 2800 BDR torque converter, 3.73 T-Lok rear, CHE rear control arms, full 2-1/2" frame w/1" jacking rails & seat supports, Rear disk brakes, Turbine wheels, All original interior w/ floor shift upgrade .......
Pretty much every panel on my 87 is new, rebuilt, or re constructed. :D
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Lets play help me figure out what's with my ignition system

Reply #10
Tape your meter to the windshield. Put the positive lead on the red wire at the ignition coil. The negative lead on ground. See if you are losing the voltage to the coil when it wont start/run.

Lets play help me figure out what's with my ignition system

Reply #11
Sounds like a bad stator pickup in the distributor. Most all vehicles have to have a tach signal(make or break signal) to collapse the the field in the coil. The positive side of the coil should be hot with the key on and the negative(tach side) should pulse during crank.
[SIGPIC][/SIGPIC]88 t-bird: 5.0ho, gt40y, crane 2031, fms 1.7, paxton@5#, aod wide ratio, tci stall, performer rpm upper, 70mm bbk, pro m 60, 42#s, 3.73 7.5" posi, jba shorties, borla, upr x. 13.4 @ 104mph. cbaza, moates, tuned by decipha

Lets play help me figure out what's with my ignition system

Reply #12
Quote from: t.birdsc;185998
Sounds like a bad stator pickup in the distributor. Most all vehicles have to have a tach signal(make or break signal) to collapse the the field in the coil. The positive side of the coil should be hot with the key on and the negative(tach side) should pulse during crank.


Yep that's what it is. Between me screwing around with it and some help on tccoa I figured it out. No I just have to find time to pull the distributor apart and change the pick up stator :hick:
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Lets play help me figure out what's with my ignition system

Reply #13
Changed the stator and the 95 works again:D



Untill the 3.8 pops a head gasket :flame:
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

 

Lets play help me figure out what's with my ignition system

Reply #14
I thought 95 had an EDIS module, not TFI. Maybe the 3.8 still had TFI? Oh and just so everyone knows, my 97 (same interior as a 95) had an updated ignition switch, not the metal bodied one that is pr0ne to fire.