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VERY RICH

  • Thread starter Thread starter GREG91GT
  • Start date Start date Jul 12, 2004

GREG91GT

Member
Jun 3, 2004
207
0
17
MISSOURI
Jul 12, 2004
#1
  • Jul 12, 2004
  • #1
PLEASE HELP my car is running very rich when i start it it runs fine for about 20seconds then it starts to load up very bad and then it will surge then i will rev it up and it will idle fine for about 20 seconds and load up again then surge,if i dont rev it up it will finaly die and starts to foul plugs if i keep starting it, and my fuel presure is at 40# at idle with ac line connected please help me out.
 

GREG91GT

Member
Jun 3, 2004
207
0
17
MISSOURI
Jul 12, 2004
#2
  • Jul 12, 2004
  • #2
dont anyone have any ideas
 

88_GT_5_oh

Sportin' a turbo 5.0 in Canadistan
Jul 4, 2004
1
0
1
WPG/MB/CA
Jul 12, 2004
#3
  • Jul 12, 2004
  • #3
new o2 sensors my car was running rich when i first got it, i put 2 new ones in and it seemed to clear it up
 
D

dude5l

Founding Member
Dec 24, 2001
201
0
0
Grande Prairie, Alberta , Canada
Jul 12, 2004
#4
  • Jul 12, 2004
  • #4
You need to get the codes out of the computer, it could be a lot of things...02 sensors, coolant temp sensor, MAF sensor etc...Without the codes you will be replacing parts for no reason.
 

GREG91GT

Member
Jun 3, 2004
207
0
17
MISSOURI
Jul 12, 2004
#5
  • Jul 12, 2004
  • #5
i do need to get new ones, but the problem did not start until i plugged my new maf in.
 
S

StonysGT

Founding Member
Jun 10, 2002
220
0
0
winamac, Indiana
Jul 12, 2004
#6
  • Jul 12, 2004
  • #6
just askin but is your MAF sensor set for your 30 lbs injectors?
 
J

jerry beach

Founding Member
May 20, 2002
2,671
0
46
Ocala,FL
Jul 12, 2004
#7
  • Jul 12, 2004
  • #7
I said this once today, and I dont want to make it sound like a cure all, but a quick test is to unplug the MAF and see if it runs better in limp mode. Dont plug or unplug it while it has power. Your car is so heavily modded, I dont know if it will run in limp mode, but it is something that is easy to check, free of charge. If this changes anything, there is a good chance your problem lies in that circuit. Especially since the problem started when you added that item. Any chance you can try the old one?
 

GREG91GT

Member
Jun 3, 2004
207
0
17
MISSOURI
Jul 12, 2004
#8
  • Jul 12, 2004
  • #8
i dont have the old one i sold it, and yes it is calibrated for 30# ,is there any chance it could be my fuel presure i dont yet have an ajustable regulator my fuel presure is 40# right now with no way to change it
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jul 12, 2004
#9
  • Jul 12, 2004
  • #9
also, no O2 input when the motor is cold (the ceramic needs to be around 500*), so if this happens cold, probably rule that out.

i like Jerry's maf idea, esp since there is some cause and effect with it.

good luck.
 

GREG91GT

Member
Jun 3, 2004
207
0
17
MISSOURI
Jul 12, 2004
#10
  • Jul 12, 2004
  • #10
i have a nother ? i do not have the s trim on the car yet,i wanted to get everything up and running before i added it on,but i do have the fmu hooked up i dont realy think this is my problem because i think it only works under high boost but i am not sure does any one else no
 
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