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

Newbie 5.0 Owner Help

  • Thread starter Thread starter johns91LX
  • Start date Start date Sep 27, 2004
J

johns91LX

New Member
Sep 27, 2004
1
0
0
Sep 27, 2004
#1
  • Sep 27, 2004
  • #1
I just recenly bought a '91 LX 5.0 Vert with 108k miles on it. It starts and runs great. No leaks, trans shifts smoothly. Heres the problem though.

I noticed that when you accelerate from a stop, the car just kinda oozes along and then all of a sudden pulls really hard. It's like the car bogs down when you try and take off. I have done plugs, wires, rotor, dist. cap, pcv valve, fuel filter and injector cleaner with no luck.

I thought maybe the trans wasn't shifting all the way down but it is. The previous owner did some stupid ***** and wired in a toyota electric fan and toyota relay with masking tape and sheet rock screws. I'm gonna rip it all out tomorrow and install an electric fan with a thermostat.

I did notice that the car isn't charging quite right. The gauge sits down on the 8 all the time even with the fan unplugged. I know I need new batt clamps but could there be a bad ground? Is my alternator shot?

I know this is long but I've waited many many years to by a vert and don't wanna spend a lot of time begin disappointed.
 

timewarped1972

Member
Jun 17, 2004
642
0
16
mesa, az
Sep 28, 2004
#2
  • Sep 28, 2004
  • #2
1; the stock charging system on these cars sucks, anything additional, like a big stereo or, in your case electric fan will further bog it down, do a search for 3g alternator conversion which is what youll need if you run an electric fan
2; theres nothing wrong with your cars sluggish performance off the line, it's an automatic tranny, they do that. see what gears you have and maybe upgrade to steeper rear end gears that helps, otherwise the only solution is to pull the tranny and install a higher stall torque converter, in which case you mught as well rebuild the tranny, in which case start saving.....lol.......
 

FrdMustangCpe

New Member
May 27, 2004
493
0
0
Sin City, NV
Sep 28, 2004
#3
  • Sep 28, 2004
  • #3
yep that fan is hurting ya. and the sluggishness will be the result of an AOD. and start stashing money for when it decides to go out. AOD + 108k miles= ticking time bomb.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 28, 2004
#4
  • Sep 28, 2004
  • #4
let us know what the battery voltage is with the car off. then again with it idling. then again at 2K rpm. parts stores will often check out the charging system for free too.

good luck.
 
9

90StangLX

Founding Member
Mar 1, 2000
419
0
16
Illinois
Sep 29, 2004
#5
  • Sep 29, 2004
  • #5
Well, from what I can tell you should expect a little sluggish off-the-line performance. a) you have a vert b) you have an AOD. Have you tried bumping the timing to 12-14*? Gears should be a priority for you, as well as an external tranny cooler. A lot of guys will tell you that an AOD at 108k miles is on its last leg, but mine lasted until roughly 187k without a cooler.
 

5.0 Nostalgia

10 Year Member
Feb 28, 2003
904
5
39
CT
Sep 29, 2004
#6
  • Sep 29, 2004
  • #6
My 91 GT convertible Auto with 3.73's did the same thing. My dad now has it and I still drive it time to time. It only had 56,000 on it when I got it. They fall on their face early but then get going.
 
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