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air-fuel ratio problem code p1131

  • Thread starter Thread starter semperfistang
  • Start date Start date Jul 19, 2007
S

semperfistang

New Member
Apr 5, 2005
47
0
0
Jul 19, 2007
#1
  • Jul 19, 2007
  • #1
in my 2002 five speed v6 mustang, i got an engine out of a junkyard and put it in last week. it wouldnt run untill i got the injector harness and fuel rail off of my old motor. dont know why, but it just wouldnt spray fuel out of the injectors. finally it ran. since then, i have had problems when im in a higher gear such as fifth. it will seem to cut out a little bit. seems like the air fuel ratio just goes way off or something. all i have to do is let out or give it a little more gas and it will stop. help me!!!


Jake
 

cjones

Founding Member
Jul 20, 2002
1,561
0
37
Avondale, AZ
Jul 22, 2007
#2
  • Jul 22, 2007
  • #2
double check all the electrical connections.

pull the codes. if you don't have a code puller or scanner, autozone will pull them for free.

does it do it at a certain throttle position?? if so, you'll want to check the TPS. the TPS is a rheostat. if a certain spot is bad, the car will act up when it passes over it.
 

raz54

New Member
Dec 21, 2006
205
0
0
Eureka Ca.
Jul 23, 2007
#3
  • Jul 23, 2007
  • #3
It could be as simple as plugs, wires, or fuel filter plugging up. Do as cjones said and check for codes first though.
 

cjones

Founding Member
Jul 20, 2002
1,561
0
37
Avondale, AZ
Jul 23, 2007
#4
  • Jul 23, 2007
  • #4
i guess i should read the title better p1131 - sensor not switching indicates lean.

first step. check all vacuum hoses and PCV for correct routing and for leaks and cracks..

next step - do you have a scanner?? we need to compare trim values. if not, we'll need to figure something else out.

have you checked the wiring to the O2 sensors??
 
S

semperfistang

New Member
Apr 5, 2005
47
0
0
Aug 4, 2007
#5
  • Aug 4, 2007
  • #5
alright i do have a scan tool. now im showing EGR flow insufficent. i was thinking about getting a sct tuner. and turning off the egr. do you think that the 1131 would go along with the 0401? thanks guys


Jake
 
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