Wrong fuel Injectors causing P1131

[vowman]

I have a 2002 Explorer sport 2 Dr. w/ 4.0 6cyl. I have had code problems since i bought this 1 year ago. I paid a local ford dealership to run a diagnostic for me and update the MAP. He said the code is due to someone replacing the fuel injectors with Flex fuel injectors instead of the matching non flex injectors. The flex fuel injectors spray .0025 where the non flex spray .018 . Has anyone heard of this happening before? I have replaced the Idle air control valve, plugs and wires, MAF, PCV and hoses. Ford wants about $1100.00 to do the job.... It starts easy when cold and acts normal but once it is warmed up it is hard to start and you can smell fuel coming out of the exhaust so It seems this is confirmed.

Any advice or knowledge would be helpful and greatly appreciated.

 

[lobo411]

I have a 2002 Explorer sport 2 Dr. w/ 4.0 6cyl. I have had code problems since i bought this 1 year ago. I paid a local ford dealership to run a diagnostic for me and update the MAP. He said the code is due to someone replacing the fuel injectors with Flex fuel injectors instead of the matching non flex injectors. The flex fuel injectors spray .0025 where the non flex spray .018 . Has anyone heard of this happening before? I have replaced the Idle air control valve, plugs and wires, MAF, PCV and hoses. Ford wants about $1100.00 to do the job.... It starts easy when cold and acts normal but once it is warmed up it is hard to start and you can smell fuel coming out of the exhaust so It seems this is confirmed.

Any advice or knowledge would be helpful and greatly appreciated.

$1100 sounds like a bargain for that job. Can I interest you in a 1996 Ford Explorer with only 160000 miles on it? A bargain at only $32,499.99!

Replacing fuel injectors is really easy. You could do that job yourself in less than 2 hours, assuming you had no experience working on the car. If you had experience, probably about an hour.

 

[2000StreetRod]

.0025 or .025?

P1131 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1

If you have the wrong flow injectors on all cylinders then codes should be present for both banks instead of just Bank 1. Also, I would think codes P0171 and P0174 would be present.
P0171 System too Lean (Bank 1)
P0174 System too Lean (Bank 2)
Injectors are normally color coded. Can you see the injectors to determine if they are all the same color? What color are they? My stock 19 lbs/hr look like this:

 

[2000StreetRod]

1l2z9f593ca

I think you should have the 24 lb/hr that look like this:

You'll probably also need the insulators (PN F77Z-9G512-AA)
since they will be brittle and break when the injectors are removed or when swapped to the new injectors.

 

[vowman]

mine are red as in your photo, the ones at the parts house are Blue. I was going to replace the seals on both ends of the injectors- is that the same as the insulators your mention. Also after I replaced the PCV and hose the codes were reset when battery was disconnected. I did have both of the other codes too i just havent drove it enough for them to pop back up i believe. thanks for the pics.

 

[2000StreetRod]

O rings vs adapters/insulators

I think the blue injectors are for export models but don't know for sure. There's an O ring at each end of the injector. There's also an adatper/insulator in the head for the injectors. Often they come out with the injectors as shown in the photo. Have the upper and lower intake manifold gaskets ever been replaced? They frequently dry out/shrink and leak resulting in lean codes being reported by the PCM. Although your symptoms sound more like the engine is running rich instead of lean. Have you checked the electrical connection to the engine coolant temperature sensor?

 

[vowman]

Dont you have to pull the intake to change out the injectors on this engine. the Ford Service manual I have says yes. I will be installing new gasgets in all those areas and will inspect for any possible vacuum leaks which could have been present before this. I will check out the temperature switch too - thanks for the heads up on that and the insulators too. I only want to do this once.
THANKS AGAIN

 

[vowman]

**UPDATE**Changed out the fuel injectors-fairly easy job for an amatuer. Found the manifold bolts on the back firewall were only hand tightened. Replaced O rings on manifold, cleaned out injector ports. It runs great now. even after warming up it starts up with a flick of the key and idles smooth. However i have the P1131 back along with a P0135. Looked up these codes and both are 02 sensor related. Even though the expense of changing all these parts has not solved my code problem I feel ok about it since there is a very noticable increase in performance.
I replaced out the bank one 02 sensor ( Bosch), checked all the wires but still have the codes. more to come.