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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Cranks but doesn't start

  • Thread starter Thread starter Ike83
  • Start date Start date Mar 11, 2010
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Ike83

Member
Sep 27, 2006
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17
St. Louis, Missouri
Mar 11, 2010
#1
  • Mar 11, 2010
  • #1
Alright, here's my situation:

I've got a 1987 GT (mods listed below) that has been sitting on my mother's business parking lot for quite awhile now. The battery died a year ago, and up until this point, I've never really had a chance to get out there and jump it/start it. That being said, the car has sat (unmolested) out on my Mom's property for a little over a year, and I figure now (with the weather starting to warm up) is a good time to get out there and get her fired up for the summer.

So, I pulled the battery out of my Taurus, and plugged it into the Mustang. However, once I turned the key, the car began to continually turn over without firing. Now, the fuel pump is working, and I smell fuel in the engine bay after I'm done turning the engine over, so that tells me that I'm at least getting fuel to the rails.

I called my buddy and he told me to pull out one of the plugs, ground it to something metal, turn the engine over, and check for a spark. I did that, and I did not get any spark. So, I tried another plug. Still no spark. I then pulled the wire that runs from the coil to the distributor off of the distributor, put a spark plug in the end of it, and checked for spark from the coil.

Nothing!

Now, on top of all this, I noticed that both spark plugs I pulled out are jet black, and some of them appear to have oil around the threads. So, could it be that I have bad valve seals, and THAT'S why I'm not getting any spark? But then, why am I not getting any spark from the coil either?

Could I potentially be dealing with two problems here, instead of just one? Or could one problem be responsible for the other?
 
S

stangbang302

New Member
Jul 13, 2007
180
0
0
fort valley, ga
Mar 11, 2010
#2
  • Mar 11, 2010
  • #2
had the same problem, replaced the tfi module and got the spark back.
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 11, 2010
#3
  • Mar 11, 2010
  • #3
stangbang302 said:
had the same problem, replaced the tfi module and got the spark back.
Click to expand...

Would this also be the reason why my spark plugs are black?
 
J

Joey7508

Member
Oct 23, 2005
198
0
17
Kerrville TX
Mar 11, 2010
#4
  • Mar 11, 2010
  • #4
any codes?
 

fiveohwblow

Official Member
15 Year Member
Jul 21, 2005
2,169
145
155
Mar 11, 2010
#5
  • Mar 11, 2010
  • #5
Coils are cheap, replace that first and get the beast to a better place to work on it.
 

Cobra1741

Member
Mar 9, 2010
152
1
16
Mar 11, 2010
#6
  • Mar 11, 2010
  • #6
module most likely....
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 11, 2010
#7
  • Mar 11, 2010
  • #7
Just run the checklist. It will save time and guessing.
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 11, 2010
#8
  • Mar 11, 2010
  • #8
Joey7508 said:
any codes?
Click to expand...

Good question. I haven't checked yet.
 
X

xtreme02stang

New Member
Jun 25, 2007
23
0
0
Orlando
Mar 11, 2010
#9
  • Mar 11, 2010
  • #9
The coil or TFI module won't cause your spark plugs to turn black. I wouldnt worry about your plugs being black until you drive your car home. Have you checked your coil or TFI yet?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 11, 2010
#10
  • Mar 11, 2010
  • #10
Coil,TFI,Pick Up coil, ignitions switch. Long list.

Better to test than blindly throwing parts at a problem.

Hissin's post is dead on.
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 16, 2010
#11
  • Mar 16, 2010
  • #11
Quick question:

If the TFI module was bad, would there not be any spark at the coil as a result? Or would there still be spark at the coil, even if the TFI module was bad?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 16, 2010
#12
  • Mar 16, 2010
  • #12
Spark signal has to pass through the TFI before it gets to the coil. Out of the PIP sensor, TFI, computer and Coil. The coil is the last to recieve the signal. The TFI actually gets the signal twice each spark signal.

TFI can be tested for free at Advanced or Autozone.
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 16, 2010
#13
  • Mar 16, 2010
  • #13
liljoe07 said:
Spark signal has to pass through the TFI before it gets to the coil. Out of the PIP sensor, TFI, computer and Coil. The coil is the last to recieve the signal. The TFI actually gets the signal twice each spark signal.

TFI can be tested for free at Advanced or Autozone.
Click to expand...

Perfect. My last question is this:

Do I need to remove the distributor entirely, in order to remove the TFI? Or is it something that can be removed while the distributor is still in place?
 
D

DREDD_LX93

New Member
Mar 1, 2010
39
0
0
Mar 16, 2010
#14
  • Mar 16, 2010
  • #14
You don't have to remove the dizzy, but you might need to turn it.
The TFI is usually pointed towards NW (from a top-view perspective), so you'll need to turn the dizzy CCW to gain access to the two screws.

You'll need a special tool to remove the two screws that connect the TFI to the dizzy, which you can buy at Autozone for 7-8 bucks. Of course, you'll also have to disconnect the electronic connections at the back of it.

To loosen the dizzy, just loosen the hold-down bold at it's base using a 13mm socket. I like to use two extensions and a univ joint for easier reach. BEFORE you loosen the bolt, mark the location of the dizzy. You want to make sure to put it back in the same location when you're done so you don't affect your timing.

A new TFI module is about $38 bucks at Autozone. It would be good to have it tested, as liljoe said.

Wish you the best.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 16, 2010
#15
  • Mar 16, 2010
  • #15
DREDD_LX93 said:
You don't have to remove the dizzy, but you might need to turn it.
The TFI is usually pointed towards NW (from a top-view perspective),
Click to expand...

Gotta see pics of your TFI orientation. If standing in front of the vehicle, the TFI should be pointing more of a south or south east direction. Or more simply, toward the front of the car, and slighty angled to the driver side head light.

South being the front of the car and east being the passenger side. Normally.
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 16, 2010
#16
  • Mar 16, 2010
  • #16
DREDD_LX93 said:
You don't have to remove the dizzy, but you might need to turn it.
The TFI is usually pointed towards NW (from a top-view perspective), so you'll need to turn the dizzy CCW to gain access to the two screws.

You'll need a special tool to remove the two screws that connect the TFI to the dizzy, which you can buy at Autozone for 7-8 bucks. Of course, you'll also have to disconnect the electronic connections at the back of it.

To loosen the dizzy, just loosen the hold-down bold at it's base using a 13mm socket. I like to use two extensions and a univ joint for easier reach. BEFORE you loosen the bolt, mark the location of the dizzy. You want to make sure to put it back in the same location when you're done so you don't affect your timing.

A new TFI module is about $38 bucks at Autozone. It would be good to have it tested, as liljoe said.

Wish you the best.
Click to expand...

Thanks bud.

I was actually able to get that mug off with a deep-well 5mm socket and a 1/4" drive. Or was it a 5.5mm?

I can't remember.

Either way, I'm pretty confident that this is the problem. The reason I say that, is because my mechanic-friend came over with his multimeter, and we were only able to read 3.5v at the TFI. According to his calculation, we should've been reading 5v.

Regardless, I'm going to take this bad boy up to the auto parts store tomorrow just have them test it to make sure. We'll know where we stand at that point, and if it is indeed the TFI module, the stang should be up and runnin' in no time.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 17, 2010
#17
  • Mar 17, 2010
  • #17
3.5v at what PIN on the TFI?
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 17, 2010
#18
  • Mar 17, 2010
  • #18
liljoe07 said:
3.5v at what PIN on the TFI?
Click to expand...

The blue one on top.

It doesn't matter though, because I've taken the module to 3 different auto parts stores, and they all said it was fine. Next, I took the coil up to the store, and apparently it's in good working condition also.

So, now I'm back to square one. The ignition box is fine, the coil is fine, the TFI module is fine...but no spark. This is FANTASTIC!

Did I happen to mention that I've got a pack of mice that have been living in my stang for several months now? Oh yeah, and there's a hole in the carpet on the passenger floor, right by where my computer is.

However, I checked all the wires on and around the computer, and I can't seem to find anywhere where the wires have been chewed.

WTF?
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 17, 2010
#19
  • Mar 17, 2010
  • #19
Top wire on the TFI should blink. If not, and the TFI test good. Then its the PIP sensor.
First....Verify that you have power at the #4 wire of the TFI with key on and cranking. And power at the #3 wire of the TFI while cranking only. Test the number 3 and 4 wires to the ignition ground(bottom wire on the TFI) when testing for power.
 

Ike83

Member
Sep 27, 2006
0
0
17
St. Louis, Missouri
Mar 17, 2010
#20
  • Mar 17, 2010
  • #20
liljoe07 said:
Top wire on the TFI should blink. If not, and the TFI test good. Then its the PIP sensor.
First....Verify that you have power at the #4 wire of the TFI with key on and cranking. And power at the #3 wire of the TFI while cranking only. Test the number 3 and 4 wires to the ignition ground(bottom wire on the TFI) when testing for power.
Click to expand...

I'll try that tonight and let you know the outcome.
 
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