eninge light codes found

[jrboatin]

99 ranger scab 4.0 4x4 auto, engine light came on and I got a scanner for xmass, pulled codes,

2 were found

P0171 bank 1
P0174 bank 2

Are these O2 sensors ?
What should be the next step ?


Thanks all.........

 

[jrboatin]

Thought I would add this, this is the codes from scanner and what it said.

DTC Information

MIL DTC

P0171 Fuel System Too Lean (Cylinder Bank 1)

Stored Codes

P0174 Fuel System Too Lean (Cylinder Bank 2)

 

[Wicked_Sludge]

check for vacuum leaks. replace fuel filter.

 

[jrboatin]

thanks,
I did replace the fuel filter about 4 months ago or 3ooo miles.
I will check for vac leaks but after buying truck I did normal stuff, and did not notice a leak but will check again.
Anything else ?

 

[Wicked_Sludge]

4.0's are notorious for developing vacuum leaks on the lower intake manifold, which can be very hard to locate. a can of starting fluid or brake cleaner is a handy tool.

 

[jrboatin]

I see what your saying.
I have seen that stuff used to locate air leaks. what
i should be doing is run at idle and spray this at the location of the manifold and the rpms should change correct?

 

[Wicked_Sludge]

you got it