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

Car is severly slow all the sudden.

  • Thread starter Thread starter 1986LX2002
  • Start date Start date Oct 25, 2004

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 25, 2004
#1
  • Oct 25, 2004
  • #1
I have no power really now, just gradualy builds power. Taking off in 1st with no wheel spin it takes forever to get up too 5K to shift into 2nd. When i floor it, the engine just seems to struggle to get past 3K. I've checked everything, plugs, wires, cap rotor, fuel filter, etc... I'm kinda lost. I ran a scanner and nothing came up so i dunno. I also noticed when i'm driving sometimes it feels like the engine cut's out for a second because the car will jerk for a sec and then be fine and then jerk again. Its really weird. I got smoked by a 2.2L stock S10 last night! Was not cool.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Oct 25, 2004
#2
  • Oct 25, 2004
  • #2
i had the same problem, it was my fuel pump.

checked your tps voltage also?
 

5LiterCOOP

Founding Member
Jun 29, 2000
392
0
16
Cincinnati, Ohio
Oct 25, 2004
#3
  • Oct 25, 2004
  • #3
88SC_GT said:
i had the same problem, it was my fuel pump.

checked your tps voltage also?
Click to expand...
I also had the same problem and it turned out to be my fuel pump. Get one of the cheap gauges and check your fuel pressure, sounds like it is most likely the pump
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Oct 25, 2004
#4
  • Oct 25, 2004
  • #4
the cutting out for a sec is a dead giveaway for my symptom.

i also had it again after a fuel pump change, and it was my tps.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Oct 25, 2004
#5
  • Oct 25, 2004
  • #5
Replace the fuel filter while you're at it.
 

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 25, 2004
#6
  • Oct 25, 2004
  • #6
The pump is about a year old. The pump is a BBK 190 unit and then a stock replacement filter from good ol autozone which i replaced in the early spring. How often do you guys change your filter? I also checked my TPS still was at .98V. I have a new air filter that went into my tune up recently. Damn car just takes for ever to get up to 5K its really weird. Had a few friends look at it and their just confused as i'am.
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
Oct 25, 2004
#7
  • Oct 25, 2004
  • #7
Yup, same problem. It turned out to be my fuel pump wiring harness conection at the tank. I ended up cutting out the harness connection and using butt connectors on each wire. Also, pay close attention when you turn the key to acc, do you hear the fuel pump kick on? Mine would kick on sometimes but not others. Get yourself a volt meter and test each side of that harness connection.
 

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 25, 2004
#8
  • Oct 25, 2004
  • #8
Man i sure hope the damn pump isnt going out already it not even 2yrs old. Well least changing the pump isnt hard if it is the problem. I'll hear for the pump to turn on when i leave for lunch.
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
Oct 25, 2004
#9
  • Oct 25, 2004
  • #9
My problem wasn't the pump, it was the stock wiring harness connection leading up to the pump. It would usually start but would cut out when driving.
 

MurdockSVT

Founding Member
Jun 7, 2002
703
0
0
Wisconsin
Oct 25, 2004
#10
  • Oct 25, 2004
  • #10
before you go about taking things apart or replacing things, clean the maf filament and try that. that sounds like a maf prob
 

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 25, 2004
#11
  • Oct 25, 2004
  • #11
its a 86GT so its Speed Density. MAF conversion is soon to come though.
 

281pony

Active Member
Aug 31, 2003
2,681
2
46
Oly, WA
Oct 25, 2004
#12
  • Oct 25, 2004
  • #12
id pretty much count on the fuel pump. several people have had the same problems.

you will hear the pump kick on if the car is starting reguardless. mine started doing the little cut out again, and it was my tps so thats why i also suggested that. at one point my fuel filter fixed it also, but the end result ended up being the pump.
 

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 25, 2004
#13
  • Oct 25, 2004
  • #13
Sorry its taken so long to reply. I'm still at work right now lol. But anyway yeah obviously i turn the key to on with out starting the engine and i hear the pump prime each time. I have a fuel pressure gauge at home. What should be the psi off the fuel rail? I lent out my repair manual to a friend still havent gotten it back yet. I also still have the stock regulator which looks pretty beat up. Thanks.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Oct 25, 2004
#14
  • Oct 25, 2004
  • #14
Pressure should be checked with the engine idling warm, and the vacuum line to the regulator unplugged from the regulator and plugged (hold your thumb over the end). Should be 38-40 psi. When you plug the line back onto the regulator it should drop down into the 32-34 unless your cam has a lot of overlap and doesn't make much vacuum at idle; that will decrease the press. difference between vacuum line being on and off.
 

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 26, 2004
#15
  • Oct 26, 2004
  • #15
Ok cool, The engine is bone stock still "nothing high performance yet " I'll check it as soon as i get back from college tomorrow.
 
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