Sorry to start new thread, but new problem, plus there was some confusion in last thread. I had just got finished with a 4cyl to v8 swap. 88 coupe with 90 motor, aod, and wiring harness with maf. Battary relocated to trunk. Everything worked fine before pulling everything. Ok, now thats out the way, at first when i first went to start, turn the key, all dash lights and dinging came on, turn the key one more to bump starter and nothing, didnt try to even crank, not even a small sound of anything doing anything. Like i didnt even turn the key over. I tried the one new battary and anther charged battary. Then hooked charger to battary and still same thing. I do NOT have the 4 prong neutral saftey switch hooked up, dont now if that is it. I have checked the starter relay/noid and it is wired right. All grounds is hooked up, from block to frame, and the one behind the back of the motor. I was told to take a screw driver from one post to the other on the relay. I did and sparks (as planned) and nothing. I tried again and no sparks and now when i turn key to anything no lights, no dingingg, no nothing. Checked all fuses under dash and none blown. Pulled computer for some fuse that isent there or i cant find, to see if its blown, cant find it. So now what??????? im lost and dont know what to do next. I need help VERFY badly, please help, with either problem, and yes the little wire on the relay is plugged up, and tried two different relays, sorry for being so long, but iwantted to give as much info, plz i really need help.
Really really P.O. New problem NEED HELP!!
- Thread starter bbkgt03
- Start date
Vipersix
Founding Member
Well first rule is never arc anything electrical with a screwdriver. Go down to the parts store and invest $5 in a remote start trigger.
Without really knowing exactly what your setup is (and assuming you've correctly assembled everything) you have most likely created a large voltage spike which has shorted a wire, relay, or fuse somewhere in your system. Electrical gremlins are THE most annoying and time-consuming problem with a computerized car as far as I'm concerned.
First thing's first, you need to check EVERY - and I do mean every - single wiring connection to ensure it is properly hooked up. I'm not entirely familiar with the '88 or '90 wiring harnesses but I'm assuming since you are not mentioning any difficulties they are very similar if not exact replications? Your starting problem very well could be attributed to dissimilar wiring harnesses. The Ford computer refuses to send a start signal to the solenoid if certain 'safety' aspects are not first met. With differing harnesses you might be running into this problem and not even know it.
Anyway, get yourself a decent digital voltmeter and begin checking all of your connections starting with the battery. Baby steps is the only way you can get anywhere in messes such as this. i.e. Good connection from battery to power relay box, good connections from relay box to computer, relay box to dash, etc. As you slowly begin to discover what is good and what is bad you can attempt to narrow other items out of the equation.
I know I didn't really give any solutions per se, but electrical problems are largely individual and difficult to diagnose without having hands on.
Good luck!
Without really knowing exactly what your setup is (and assuming you've correctly assembled everything) you have most likely created a large voltage spike which has shorted a wire, relay, or fuse somewhere in your system. Electrical gremlins are THE most annoying and time-consuming problem with a computerized car as far as I'm concerned.
First thing's first, you need to check EVERY - and I do mean every - single wiring connection to ensure it is properly hooked up. I'm not entirely familiar with the '88 or '90 wiring harnesses but I'm assuming since you are not mentioning any difficulties they are very similar if not exact replications? Your starting problem very well could be attributed to dissimilar wiring harnesses. The Ford computer refuses to send a start signal to the solenoid if certain 'safety' aspects are not first met. With differing harnesses you might be running into this problem and not even know it.
Anyway, get yourself a decent digital voltmeter and begin checking all of your connections starting with the battery. Baby steps is the only way you can get anywhere in messes such as this. i.e. Good connection from battery to power relay box, good connections from relay box to computer, relay box to dash, etc. As you slowly begin to discover what is good and what is bad you can attempt to narrow other items out of the equation.
I know I didn't really give any solutions per se, but electrical problems are largely individual and difficult to diagnose without having hands on.
Good luck!
No Crank checklist for 5.0 Mustangs
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…
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 while trying to start the car: more than .5 volts across a connection indicates a problem.
See http://www.fluke.com/application_notes/automotive/circuit.asp?AGID=1&SID=103 for help for help troubleshooting voltage drops across grounds.
1.) Will the car start if it is jumped? Then clean battery terminals and check battery.
2.) Check the battery to engine block ground, and the ground behind the engine to the firewall.
3.) Jump the big terminals on the starter relay 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.
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 starts, 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
See http://www.autozone.com/images/cds/gif/large/0900823d80195963.gif for 88-90 year cars
See http://www.autozone.com/images/cds/gif/large/0900823d80195964.gif for 91-93 year cars.
See http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-95 model cars.
6.) The starter may be hung, loosen up the bolts that hold it on, and give it a good whack with a big hammer. Tighten up the bolts and try again.
7.) 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 upgraded high torque mini starter.
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…
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 while trying to start the car: more than .5 volts across a connection indicates a problem.
See http://www.fluke.com/application_notes/automotive/circuit.asp?AGID=1&SID=103 for help for help troubleshooting voltage drops across grounds.
1.) Will the car start if it is jumped? Then clean battery terminals and check battery.
2.) Check the battery to engine block ground, and the ground behind the engine to the firewall.
3.) Jump the big terminals on the starter relay 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.
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 starts, 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
See http://www.autozone.com/images/cds/gif/large/0900823d80195963.gif for 88-90 year cars
See http://www.autozone.com/images/cds/gif/large/0900823d80195964.gif for 91-93 year cars.
See http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-95 model cars.
6.) The starter may be hung, loosen up the bolts that hold it on, and give it a good whack with a big hammer. Tighten up the bolts and try again.
7.) 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 upgraded high torque mini starter.
Ok, i will start to check the volts, is there any clue to what would have blown, a certain fuse in a certain place? All the 5-30 amp fuses in the fuse box under dash is fine, the car is still acting dead, still no power to anything, also the shift linkinge on the tranny, is Park all the way forward towards the front, or all the way back towards the tailights? and again does it matter if the nuetral safty switch is plugged in? would that stop it from running? trying not to panic but wiring drives my insane, and not even knowing where to start is worse, i labled EVERYTHING before i swapped so it wouldent be a huge mess.
mustangfan1990
New Member
If you took a screw driver and arced the right terminal it bypass everything and puts power straight to the starter. There fore if you do this and nothing happens your problem lies between your starter solenoid and your starter ( or dead battery which you said you put a new one in)
Also I would imagine on an AOD car that you would need the Nuetral safty switch. My car use to be an automatic and it wont crank unless it is in park or nuetral. why didnt you hook it up?
Also I would imagine on an AOD car that you would need the Nuetral safty switch. My car use to be an automatic and it wont crank unless it is in park or nuetral. why didnt you hook it up?
1987stangman
Member
- Jul 12, 2006
- 684
- 24
- 19
Car was an auto, but i swapped all of the wiring, i did get the power yeasterday, was blown starter relay, but still no crank. In the haynes manual it says the starter relay should "click" and its not which makes me think its the Nuetural start switch on the tranny, the only reason i wanted to know if it would start without it is i just put the tranny in, and dont want to have to remove the h pipe, driveshaft, and lower tranny a little just to plug it in, i wanted it to start first, which i still cant get that question answered. I checked all volts today (took forever) and everything looked good, anther question is to jump the relay, does the ignition have to be turned on, and/or does the little wire that hooks to the screw on the relay have to be hooked up? this will tell me if the starter is the problem, thanks
dgollem
20+ Year Stangneter 
Do you have the clutch pedal safety switch wired up? A factory stick car will not crank if the clutch is not depressed. If you didn't install the switch during your swap you will have to find the connector and bypass it so the car will crank. The only danger with a bypass is the car will crank and may start while in gear. If this happens she'll take off on you.
The key should not need to be on, to jump the starter relay, if the key is off it should still crank it just won't start
Again jumping the starter relay with the car in gear could be a bad thing, if the starter cranks with the car in gear the car is going to move. Refer to Jrichker's post pancaking yourself will not fix the problem.
The key should not need to be on, to jump the starter relay, if the key is off it should still crank it just won't start
Again jumping the starter relay with the car in gear could be a bad thing, if the starter cranks with the car in gear the car is going to move. Refer to Jrichker's post pancaking yourself will not fix the problem.
capri debris
Member
Like mentioned above, the problem is probably with your starter. And YES, you need a neutral safety switch... no way around it unless you twist the wires that go to it together so it's always in the closed position. (I do NOT advise this, because you will be able to start the car when it's in 1, D or OD... not a good idea.)
Go down this check list.
CHECK:
1. Power from battery to starter relay.
2. Power from starter relay to starter.
3. Ground wire from block to battery.
4. Ground from block to chassis.
If all this checks out OK and you use a screwdriver to jump the two posts on the starter relay (this will not hurt anyting) and still nothing... then the starter is crap.
If you can get the starter to kick over using a screwdriver on the relay posts, but it won't kick the starter using the key... then the problem is in the ignition wiring or switch.
Go down this check list.
CHECK:
1. Power from battery to starter relay.
2. Power from starter relay to starter.
3. Ground wire from block to battery.
4. Ground from block to chassis.
If all this checks out OK and you use a screwdriver to jump the two posts on the starter relay (this will not hurt anyting) and still nothing... then the starter is crap.
If you can get the starter to kick over using a screwdriver on the relay posts, but it won't kick the starter using the key... then the problem is in the ignition wiring or switch.
mustangfan1990
New Member
MY car did this yesterday and I thought about this thread...lol I couldnt fiqure it out. I would turn the key and all the lights would come on and then turned it to crank it and nothing and after that the lights wouldnt even come on. So I turn my key to the on positon and left it. I got out og my car and checked my battery cables (clean them and made sure they was tight) Then I shifted over to the starter relay and started tightening the nut that holds the pos battery cable on and I heard that loud ass Vortech 255 pump come on and I knew then that was problem. My cable termnal that connected to my starter relay was rusted real bad I cleaned it and problem fixed
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