99 Gt no power above 4,000 rpm

C

CMEFLY

New Member

Dec 11, 2003

64

0

0

bonney lake WA.

Feb 20, 2008

#1

• Feb 20, 2008

• #1

I finally made the jump from 5.0 mustangs to 4.6. But I am having trouble with the new ride. It has 118,000 miles and a 5 speed. It flat out falls on its face at 4,000 rpm and if i am at full throttle it wont go any higher but if i ease into the throttle it wil rev higher. No codes and it will rev normal with no load. Definitly worse up hill. I have changed the fuel fiter with a motorcraft filter. Any ideas woud be greatlly appreciated. Thanks, Mike

 

blkhorse

Founding Member

Oct 30, 1999

345

1

18

Feb 20, 2008

#2

• Feb 20, 2008

• #2

fuel pump

 

F

ForPointSex

Founding Member

Mar 19, 2002

395

0

16

Mercer, NJ

Feb 20, 2008

#3

• Feb 20, 2008

• #3

My did the same thing when the fuel pump was bad. I replaced it with a SVT focus pump and it runs good now.

 

ADRENLN

Active Member

Apr 16, 2003

2,342

3

49

NJ

Feb 20, 2008

#4

• Feb 20, 2008

• #4

yea somthin is wrong fuel wise, that is where the 4.6 makes all its power.

 

96GTstang46

New Member

Nov 20, 2006

142

0

0

Seattle, Washington

Feb 21, 2008

#5

• Feb 21, 2008

• #5

I experienced a similar problem when i had a clogged cat. I had a high flow cat just puke out on me and it didnt seem like it ran funny UNTIL i opened it up and whenever it got close to 3-4000rpms so.. if you have checked everything else, might be something else to look at.. Just my .02

 

TrueBlue03

Member

Dec 9, 2003

372

3

18

Bay Area, CA

Feb 21, 2008

#6

• Feb 21, 2008

• #6

Check Mass airflow sensor
Fuel pump
Spark plugs

mine was bogging bad when i got on it above 3500 rpms.
1st thing i tried was changing fuel filter...which i see you already did.
Then I changed the spark plugs and cleaned the mass airflow sensor. That did the trick.

 

J

justinschmidt1

Member

Jun 15, 2005

349

0

16

Feb 21, 2008

#7

• Feb 21, 2008

• #7

yea my 96 did this stock

 

Mossberg

Active Member

Jul 21, 2003

0

1

36

ATL, Shawty

Feb 22, 2008

#8

• Feb 22, 2008

• #8

justinschmidt1 said:

yea my 96 did this stock

Click to expand...

Stock NPI Stangs FTMFW!

 

DBMSTNG

I fantasize about it being BIG!

Founding Member

Apr 23, 2002

2,120

0

56

not quite here

Feb 22, 2008

#9

• Feb 22, 2008

• #9

in addition to what has already been said, check the fuel filter and run injector cleaning.

 

C

CMEFLY

New Member

Dec 11, 2003

64

0

0

bonney lake WA.

Feb 28, 2008

#10

• Feb 28, 2008

• #10

Just wanted to give a update. I replaced the fuel pump with a focus pump and it runs great again. Thanks for the help.