If the redneck smoke test doesn't reveal anything it's likely the injector o-rings.

 

That would be impossible in my case. I replace all o-rings and all the intake and valve cover gaskets. My check light was good for 2,000 miles after the work, then came back.

 

Nooooo!! It's back MPDano? What's your plan?

 

Smoke test Andy. I have to resolve this before my smog test in 2017, plus tired of looking at the check light "and" 3 amigos.

 

I have a question about the secondary air inlet (upper intake manifold), does this need to be block if there is no secondary air installed? Mine has a piece of broken rubber on in, like there was once something installed but there is definitely nothing installed now, would this cause the lean codes?

 

I Have a Disco 2 V8 Auto that is bringing up P0171 and P0174, smoke tested and all seems to be fine, MAF values look okay, Long Fuel Trim is stuck on +%25, it never moves. What I did notice is that before putting the vehicle in Idle the LFT is already in 25% (both banks). Any Ideas? or is this suppose to be?

 

Check your SAI solonoid isn't on the fritz.

http://www.roverparts.com/Parts/YDJ100000G

Mine wasn't activating properly and throwing those codes. You can apply 12v directly to it, you should get a very positive, clean click.

 

Thats interesting, there is no SAI installed, although I wonder if there was one as there was a piece of pipe broken of on the Plenum (where the SAI should feed the air intake) before I capped it as I thought that could have contributed to a Vacuum leak. How do I know if there was SAI installed previously (I have only had the Disco for a year)?

 

I don't not have SAI but I bought an engine that did. If memory serves the SAI just goes to the heads, not the plenum. It injects air directly into the heads.

The pipes on the intake, facing the engine from the front, are vacuum lines (you can cap the one toward the back, left). . On the right you have cooling lines (front. You can also cap), purse and idle air (behind throttle body and top of intake, on the back).

 

Sorry Charlie_V don't know why I said Plenum, but you are correct the Upper air intake. Basically you are saying though that it shouldn't matter if the Disco had a SAI and is now removed. There is nothing else that is needed to be done? The thing is with these codes, I don't get any running problems except response, power and Consumption.