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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

to lean??

  • Thread starter Thread starter JPstealth
  • Start date Start date Jan 19, 2008

JPstealth

Member
Nov 21, 2007
34
0
7
Nothern NJ
Jan 19, 2008
#1
  • Jan 19, 2008
  • #1
ok, heres my dilemma... my car is a 00 GT with 60k miles. The engine light is reading lean in bank 1 and bank 2 and i cant figure it out. The car also idles erracticly.

it has C&L intake and maf, reichard intake manifold, full exhaust and a few more normal goodies.

so far i have:
cleaned the K&N filter, the entire intake, and MAF.
I have also checked for vacuum leaks and found a couple small ones which i fixed.
I changed the IAC
put injector cleaner through it

car seems to run fine when driving but i did notice a slight whining in the back of the car at idle, could this be the fuel pump going bad? would that contribute to a poor idle though?

any other suggestions?
 

the98stang

Active Member
Aug 12, 2005
2,408
0
47
Clovis, CA
Jan 19, 2008
#2
  • Jan 19, 2008
  • #2
lean codes could be triggered by a faulty o2 sensor.
 

urban96

bubb rubb says:"woo woooooo"
Founding Member
Sep 24, 2002
3,464
1
69
Syracuse, NY
Jan 19, 2008
#3
  • Jan 19, 2008
  • #3
could be the aftermarket MAF
 
K

Ken01GTvert

Member
Aug 27, 2003
175
0
16
Colorado
Jan 20, 2008
#4
  • Jan 20, 2008
  • #4
When did you start throwing codes? Have you had a tune since you added the C&L intake, MAF and K&N combination? I was throwing codes when I went to that set up. I didn't want to get a tune so I replaced the C&L MAF and K&N with the stock MAF and Filter/housing with the rubber nose pulled off and then no more codes being thrown.
 
S

SilverBullet00

New Member
Jul 5, 2004
1,150
0
0
Wichita, KS
Jan 20, 2008
#5
  • Jan 20, 2008
  • #5
I have heard a lot of bad things about non FORD (or SCT) MAF's I would pull it off and try to run the stocker..
 

urban96

bubb rubb says:"woo woooooo"
Founding Member
Sep 24, 2002
3,464
1
69
Syracuse, NY
Jan 20, 2008
#6
  • Jan 20, 2008
  • #6
a custom tune would easily cure that

i havnt heard many good things about c&l mafs. they with the 5.0's it seems to be hit or miss with idle problems
 

JPstealth

Member
Nov 21, 2007
34
0
7
Nothern NJ
Jan 21, 2008
#7
  • Jan 21, 2008
  • #7
yea, the car has no tune. This maybe is an excuse to go get one Other wise, ill see if I can get my hands on a stock maf and switch it out and cross my fingers.
 

joshheat25

Member
Nov 8, 2004
871
0
16
Delaware
Jan 21, 2008
#8
  • Jan 21, 2008
  • #8
I have the same C and L intake and I also have an aftermarket tb and upper plentum and I have o/r exhaust when I took it to get it tuned it was over 25% lean on startup. I was throwing codes just like you wondering wtf. I had a hand held tuner and still was lean. I got a tune and now I'm fine! either get a tune or put the stock stuff back on.
 

Stormer

New Member
Jan 8, 2008
7
0
0
Lakeland Florida
Jan 22, 2008
#9
  • Jan 22, 2008
  • #9
I hate to admit this... but it may help you;

I was having a similar problem with my 2003 GT, I also just turned over 60,000. I have a MAC 85mm Cold Air Intake system and when I put it on my engine started throwing lean codes in both banks and had difficulty starting. I cleaned out my sensors checked the vacuum hoses and had a diagnostic run and it still didn't fix the problem. I put the stock box back on and my codes went away. After a few weeks it crossed my mind that it had been some time since I had the fuel filter changed. (supposed to do it every 12,000 miles) I took it to the shop the following day and had it replaced put my CAI back on and have been running almost a week with no problems and a lot better power!
 

9646gt

Member
Apr 7, 2005
595
3
18
Holloman AFB,NM
Jan 22, 2008
#10
  • Jan 22, 2008
  • #10
Tune would be best bet, if the MAF is clean and all it should fix it. I don't think it's a faulty 02 sensor , wouldn't that throw a code?
 
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