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loss of power with more throttle

  • Thread starter Thread starter Torinalth
  • Start date Start date Jul 3, 2006
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Torinalth

Founding Member
Jul 16, 2002
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Clayton NC
Jul 18, 2006
#21
  • Jul 18, 2006
  • #21
ok, had to resurrect the thread... it happened again. i think i finally have the formula. it needs to be HOT around 95+ driving for more hten 2-3 hours strait and have less then 1/3 tank of gas. somewhere along this equasion of what leads up to my issue all these items are met and its typically on the highway going over 60 and then blam, i cant accellerate anymore to pass other cars.

today it got progressivly worse very fast where i could not even keep a constant 40mph in 4th 3rd or 2nd gear... when it gets like this it WILL stall out on me if its not in gear with the momentum keeping the car moving... clutch in and the rpms drop fast and instant stall. so far only fixes are to let it sit for minimum of 10 min and that buys me around 20 min driving time, ro a few hours and it goes away for about the same time. the interesting thing is that if i fill up the tank to full with new gas, it is fine.... again till i get down below 1/3-1/4 tank and a very hot day with lots of driving.

possibly pump going out? i really am having a hard time figuring this out.

going to reclarify the exact symptoms: when driving i gradually lose how much power i can harness. it starts with not being able to accellerate hard (more then 3/4 throttle) and when i do it falls on its face as if i am barely touching the throttle. its not a sputter, its an instant drop like i turned the key off. the farther i go the more power i lose, and i cant get passed 1/2 throttle, and finally cant maintain speed in any gear in any RPM.

thoughts? SVTTECH? anyone? i drive my car for a living, and dont have any other vehicle, so this is really getting difficult on the work front.

Torinalth
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
134
Jul 18, 2006
#22
  • Jul 18, 2006
  • #22
Could it be clogged fuel filter or fuel pump intermittent failure?

Did you ever SeaFoam it? I do not think SeaFoam hurts the plugs, probably helps to clean them a bit IMHO.

But I think your problem is fuel related not spark related.

I think you should change the fuel filter.
 
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Torinalth

Founding Member
Jul 16, 2002
952
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Clayton NC
Jul 18, 2006
#23
  • Jul 18, 2006
  • #23
i am leaning that way... filter was replaced less then 15k ago. i am starting to think its the pump either shorting or... overheating somehow? when the tank is full it never seems to do it, run it lower and it does it.... tomorrow is going to be a scorcher... going to keeo the tank above 3/4 all day and see if it happens.. then going to keep it low all day thursday and see if it does it. but i think you are corect in thinking the pump.. and the seafoam has not gone through it yet... trying to make friends with all my new neighbors before i smoke them out....

Torinalth
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
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89
the people's republic of massachusetts
Jul 18, 2006
#24
  • Jul 18, 2006
  • #24
check your fuel presure with either a scan tool with live data or a mecanical guage on the schrader valve...

I am 99.999999999 9/10 percent sure that your fuel pump is the problem, without fuel presure readings I can not be sure but thats what it sounds like to me.
 
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Torinalth

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Jul 16, 2002
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Clayton NC
Jul 19, 2006
#25
  • Jul 19, 2006
  • #25
well, ordered the new GT40 pump from randy. should be here friday for a weekend install. figured i'd spend the 80 to get the pump, hopefully fix the problem and get more headway for when i get my KB as well... any suggestions on pump install?

Torinalth
 

RoadKill96

New Member
Mar 1, 2006
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0
Victorville CA
Jul 19, 2006
#26
  • Jul 19, 2006
  • #26
I am haveing the same prob but the scope said its my O2 sencers and my MAF or VAF whats a VAF?
 

Built98GT

New Member
Oct 17, 2005
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OKC
Jul 19, 2006
#27
  • Jul 19, 2006
  • #27
I would also have to think your fuel pump is the problem. I would also recommend you start using 91 octane or above gas.
 
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Torinalth

Founding Member
Jul 16, 2002
952
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Clayton NC
Jul 19, 2006
#28
  • Jul 19, 2006
  • #28
I'm already running 89.. no way i am going to 93 octane without a blower or a tune for it.

I have had intermittant troubles with the passenger downstream o2 sensor but nothing serious. doesnt seem related, at least for my end. we will see how it all works out come this weekend when i can do the install.

Torinalth
 

RoadKill96

New Member
Mar 1, 2006
39
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Victorville CA
Jul 20, 2006
#29
  • Jul 20, 2006
  • #29
Fixed the prob try changeing your dis cap and rotor
and clean the air filter my 90 mustang run really fast again Oh and th EGR valve was clutterd with carbon i only spent 25 bucks on an accel cap and rotor at autozone
 
T

Torinalth

Founding Member
Jul 16, 2002
952
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Clayton NC
Jul 20, 2006
#30
  • Jul 20, 2006
  • #30
sorry, no dis on the 99+.... so thats kinda out. air filter is clean. i am going to check the EGR this weekend as well, but doubt its that.

Torinalth
 
R

RoadconeTuning

New Member
Apr 4, 2006
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Upstate, SC
Jul 20, 2006
#31
  • Jul 20, 2006
  • #31
change the damn fuel filter... 15k is long enough for trash to clog it... also it could be one of the coils goin out somewhat when hot... you really need to throw a scanner on that thing to see whats going on... just replacing parts is gonna cost you a lot of money and frustration.
 
T

Torinalth

Founding Member
Jul 16, 2002
952
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16
Clayton NC
Jul 20, 2006
#32
  • Jul 20, 2006
  • #32
threw a scanner on it... o2 sensor was the only stored code since i replaced my plugs. got a new 02 sensor, fuel filter (due to your lovely prodding), and my GT40 pump as well (will need more fuel when i go FI anyhow). will do it all prolly saterday, or maybe sunday.

question i do have. for the 02 sensor... sensor 2 bank 2 is down stream... but what side... passenger i am guessing, but dont for sure know.

also, when i replace the pump i am wanting to try and clean out the tank as well... does anyone have any suggesstions for how to do it... i dont think you can seperate the tank, so do i have to work through ther fuel pump hole? just use water and spray it out? paper towels? brushes? just trying to see what others have done.

Torinalth
 
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