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

Problem in High Gear

  • Thread starter Thread starter zingi4532
  • Start date Start date Sep 10, 2004
Z

zingi4532

New Member
Dec 30, 2002
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0
Sep 10, 2004
#1
  • Sep 10, 2004
  • #1
I have a problem with my 90 5.0 that started a few month ago. When I'm cruising on the freeway in 5th and mash down the gas, the engine seems to "stumble", it did not use to do this. It kind of feels like it's missing but it only does it in 4th and 5th under WOT. Cruising aroung normaly, it seems like it has normal power- the problem is only in high gear. Do you guys have any suggestions?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 10, 2004
#2
  • Sep 10, 2004
  • #2
have you pulled codes? i would pay attention to the EGR. good luck.
 
B

battyice

New Member
Mar 7, 2004
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West Chazy, NY
Sep 10, 2004
#3
  • Sep 10, 2004
  • #3
Is your engine in good tune? Neglected ignition components like plug wires & the cap & rotor can cause problems like you're describing.
 
Z

zingi4532

New Member
Dec 30, 2002
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Sep 21, 2004
#4
  • Sep 21, 2004
  • #4
The engine is in great shape. It only has 82k on it. I did a tune up a few month ago. I put in an accel cap & rotor, FMS 9mm plug wires, new plugs and a new egr sensor to pass emissions. i pulled the codes at that time to see why my check engine light was coming on and when i changed out that sensor the light went off- i haven't gotten any check engine lights since. The car has 3.55's and a new FMS wcT-5, aluminum drive shaft, High flow air filter and bbk pullies. Do you guys think it's the fuel filter- somebody mentioned that. What kind of plugs/gap do you guys go with cause i'm thinking of changing out the rapid fires that are in there right now. Any other suggestions would be greatly appreciated.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Sep 21, 2004
#5
  • Sep 21, 2004
  • #5
my car has done similar things and a fuel filter has been a temporary fix. its an easy thing to replace, has it ever been replaced before? i would try that.

for 89 and 90 my chilton says .044 gap, but for 91-93 its saying .054
 
Z

zingi4532

New Member
Dec 30, 2002
9
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0
Sep 21, 2004
#6
  • Sep 21, 2004
  • #6
The fuel filter has not been changed in a few years- that sounds like a likely problem- I'll replace that and see what happens; btw what kind of spark plugs do you guys like to use on a stock motor
 
R

rock88gt

New Member
Sep 19, 2004
13
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0
North Carolina
Sep 21, 2004
#7
  • Sep 21, 2004
  • #7
Are you still using stock injectors? If you have bigger injectors you may need a better fuel pump or just adjust your fuel pressure. Are you sure it's the engine and not your transmission slipping?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Sep 21, 2004
#8
  • Sep 21, 2004
  • #8
zingi4532 said:
btw what kind of spark plugs do you guys like to use on a stock motor
Click to expand...
autolite 25's for me. Motorcrafts are good too. some folks have had problems with platinums (just something to remember if you try some and have issues).

good luck.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Sep 21, 2004
#9
  • Sep 21, 2004
  • #9
i use autolites also.
 
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