End of my tether.... Please Help!!

[turnbulltj]

Good evening Guys,
I am in the UK with a 2000 Ford Explorer North Face.
I am totally bamboozled with a lumpy idle and power loss problem.
I have had the following done,

HT Leads
Plugs
Valves checked
Inlet manifold gasket
Timing Chains
Lambda/Hego Sensors
Catalytic converters
ECU
MAF Sensor
Air leaks checked

The computer keeps throwing the Engine management light with a lean code, but cannot rectify. I am at my wits end and out of cash.
Any ideas.

Trev

 

[2000StreetRod]

Both banks lean?

Do the diagnostic trouble codes indicate both banks are lean? If not, which one is lean?

Did you clean/replace the IAC valve?

Have you checked the PCV valve?

Did you replace the upper and lower intake manifold gaskets or just the upper?

Have you checked the variable induction system to make sure it is switching intake runner length back and forth?

Do you have exhaust gas recirculation (EGR)? If so, is the EGR valve closing at idle and WOT?

Have you tested the fuel pressure?

 

[ThePhoenix]

Did you replace the upper and lower intake manifold gaskets or just the upper?

Did you replace the upper and lower intake manifold gaskets or just the upper?

Did you replace the upper and lower intake manifold gaskets or just the upper?


I cant say this enough.....

 

[turnbulltj]

Did you replace the upper and lower intake manifold gaskets or just the upper?

Did you replace the upper and lower intake manifold gaskets or just the upper?

Did you replace the upper and lower intake manifold gaskets or just the upper?


I cant say this enough.....

Just the Upper

 

[ThePhoenix]

d'oh

I did both and it smoothed me out. It took all darn day but only cost $35 or so