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Help! Mystery problems

  • Thread starter Thread starter Horsepower67
  • Start date Start date Mar 25, 2004
H

Horsepower67

New Member
Feb 1, 2004
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Mar 25, 2004
#1
  • Mar 25, 2004
  • #1
Hey guys, here's the oddities with my 89 GT vert.
Not many mods that affect the drivetrain, mostly suspension. Just (mm FMS wires, Crane coil,

It cranks fine, idles nice and smoothly, runs very smoothly, but.....

It tends to bog a lot below 2000, and when you shift gears, (think major turbo lag...) and it's as if you're asking the world of it to go over 3500. It's really only comfortable between 2000-2800.

Anytime you try to get into it, or accelerate while driving there's a sound like a vacuum leak (doesn't have one) or more like an exhast leak on the headers. (replaced a few times, high quality gaskets.)

Often has a "gasey" smell when you stop. Usually this is noticable if the vents are on.

Dunno it this means anything, but the car has Hooker Super Comp shorties, Mac cat H-Pipe, and Cobra/LX style Flowmaster "American Thunder" catback. BUT, it's very quiet at all RPMS, except between 2000-2800 which is where is is on the freeway (droning incredibly loudly and driving me insane....)

Basically, it's a very reliable and smooth running 5.0, just incredibly unresponsive.....
HELP! any ideas guys? I know it's just something minor, it just feels like something is off and hold ing it back!
 

50Dreamer

Founding Member
Nov 14, 2000
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Mar 25, 2004
#2
  • Mar 25, 2004
  • #2
check your fuel pressure
 
H

Horsepower67

New Member
Feb 1, 2004
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Mar 25, 2004
#3
  • Mar 25, 2004
  • #3
42 psi at idle
 

shawn13

New Member
Feb 28, 2004
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Dwight IL
Mar 25, 2004
#4
  • Mar 25, 2004
  • #4
did you check the timming sounds like it try to work to hard I got headers off road h pipe american thunder all the way out and its loud as hell cant even hear the fuss buster go off :]
 

jrichker

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Mar 25, 2004
#5
  • Mar 25, 2004
  • #5
The gassy smell is probably from a disconnected or damaged carbon canister. If someone disconnected it and failed to plug the vacuum line, it will make a vacuum leak.

Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html
 
H

Horsepower67

New Member
Feb 1, 2004
62
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0
Mar 25, 2004
#6
  • Mar 25, 2004
  • #6
Well, I'm wrong... Fuel is more 33 PSI... Think an adjustable regulator is what I need or a new pump? It is pretty noisey....
I have a Vortec T-Rex external, is that too much? Will it affect the mileage assuming nothing else changes? It's going to be a while before the drivetrain get much more aggressive, should I swap then T-Rex with someone for an internal pump? If I use the T-Rex, should I leave the stock internal in place, or remove it?
The T-Rex would go before the filter right?

I took a close look at the charcoal canister, and yup, stupid line had come loose. No more gasey smell!
Now just have to get the responsiveness back....
 
S

sublime29

New Member
Mar 18, 2004
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0
Mar 25, 2004
#7
  • Mar 25, 2004
  • #7
You should be fine with the t-rex and it should be after the filter.So the fuel is clean before entering you fuel pump.I would be way easy to just get a higher pressure then stock fuel pump.You would have to diconnect the stock one I think and cut and splice the t-rex in.I don't know if the car will run without the stock pump pluged in.I would get a walpro fuel pump they are cheap like a 155 should be good.Since you have a reulator the car will only get the fuel it needs know matter how big the pump.
 
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