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Electrical Issue

  • Thread starter Thread starter 88-GT
  • Start date Start date Nov 9, 2004

88-GT

Member
Oct 8, 2004
183
2
18
Nov 9, 2004
#1
  • Nov 9, 2004
  • #1
Hey guys

Well pretty new to the site and new to mustangs also. Well I bought my first stang about a week ago and have already run into problems...The car has 180 000 km on it and seems to have sum electrical issues. It is a speed density car. Well the problem is hard for me to diagnose rite now as it needs to be certified so I cannot drive it. It starts great but if it sits and idles for about 5 mins, it runs great, idles smooth, and from when I have driven it has lots of power, but after it gets to operating temp it starts to run rough and then subsequently dies less then a minute after. Then when I try to start it it will weakly fire and the tach will jump all over the place, its almost as if its diesling out....I have no idea to the source of problem but its really scaring me. Another thing I noticed is it is a bit hesitant when u rev it from idle, related or not im just letting you know. Any help would be greatly appreciated.

Adam
 

88-GT

Member
Oct 8, 2004
183
2
18
Nov 9, 2004
#2
  • Nov 9, 2004
  • #2
Edit:

well I just went outside and after leaving it for about half an hour to cool down it started rite up and runs fine....I guess this leaves me to believe that it is sumhow temperature related...really finicy TFI module maybe?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 9, 2004
#3
  • Nov 9, 2004
  • #3
TFI is an issue - good idea. parts stores can bench test them for ya. i would do lots of testing, since the unit might need to be hot to fail.

have you pulled codes? you can do it with a test light (your SD car likely does not have a functional CEL).

good luck.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
Nov 10, 2004
#4
  • Nov 10, 2004
  • #4
TFI is a good guess, and after that the pickup coil in the distributor.
 

88-GT

Member
Oct 8, 2004
183
2
18
Nov 10, 2004
#5
  • Nov 10, 2004
  • #5
I guess my next question is where is the TFI module? as I said VERY new to mustangs...I got the impression its on the distributar..am I right? Thnx

Adam
 

OL' WHITEY

New Member
Jan 28, 2004
273
0
0
Weddington, NC
Nov 10, 2004
#6
  • Nov 10, 2004
  • #6
Yup! The TFI module is the plastic box that the wires plug into. you can remove this box with a deep well CRAFTSMAN socket. If you don't have CRAFTSMAN, you might have to buy the removal tool from the parts store to get it off. I don't remember the socket size, sorry.
 

NCStang86

New Member
Mar 21, 2004
80
0
0
selma,nc
Nov 10, 2004
#7
  • Nov 10, 2004
  • #7
Converting to mass air will solve alot of your rough running problems.I converted my 86 to mass air about 10 yrs ago and that was some of the best money I ever spent.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
Nov 10, 2004
#8
  • Nov 10, 2004
  • #8
Another thing to do is to remove your Idle Air Bypass (IAB) valve from the side to the trhottle body and clean that baby out REALLY good. If there is a lot of gunk in there, it indicates that the PCV valve at the back center of the lower intake is not working right AND/OR the wire screen below the PCV valve is completely plugged with gunk - which is quite common. The IAB ensures a good smooth idle. Use small tools and pipe cleaner or whatever to get that thing reallyu clean inside. It is a solenoid valve, so the solenoid must operate very smoothly.

I don't think ANY of your problems would be cured by converting to MAF. I still run speed density.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 10, 2004
#9
  • Nov 10, 2004
  • #9
i think the TFI socket is 5.5MM. one would need a thin walled socket to do it w/o the tool.
 

tmoss

Gettin Wired
Founding Member
Jun 28, 2001
7,153
32
128
Saint Louis, MO
Nov 11, 2004
#10
  • Nov 11, 2004
  • #10
The tool is real cheap at Autozone or other suppliers. I keep a TFI spare and the tool in a parts kit in my trunk all the time. Kit includes TFI, EEC/Fuel pump relay, o-rings for fuel system and injectors, cap, rotor, spare ACT, ECT, and DA1 computer.
 

88-GT

Member
Oct 8, 2004
183
2
18
Nov 11, 2004
#11
  • Nov 11, 2004
  • #11
Well I just finished installing the new TFI and it runs perfect, no hesitation or sputtering and no stalling out. And once shut off will start instantly. So looks like I found my problem so thanks to everyone that helped me out.

Adam
 
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