Running lean w/o boost HELP

[archenemy236]

Well last night we changed the Fuel filter the one that was on it was so plugged weighed almost 4 x more than the new one...but it still is doing the exact same thing...tonight we are going to try re-soldering the MAFS and also clean them...I hope one of these things works...

[Skym]

Change fuelfilter every 20,000km. Even after that amount of km fuelfilter has alot of crap inside. Did you check fuelpressure afterwards??, as clogged fuelfilter can make fuelpump work harder, fail. Should be around 35.5psi or so at idle with FPR vacuum hose connected for RB26, RB20 engine.

[archenemy236]

We didnt have access to a gauge, I will try and get my hands on one tonight.

[archenemy236]

Alright just cleaned the MAFS and also checked the solder and the solder looks mint...after resetting the ECU I fired it up and its doing the exact same thing...So once i drove it around a little i pulled the codes off the ECU and its coming up with a 1 single long blink and 2 fast afterward which is "12 - Air Flow Meter" so this could mean its a MAF or a vacuum leak correct?

[M13]

My car pulls nicely and smooth.

I replaced the O-rings on injectors to OEM for a better fit but it still has 1/16th of an inch vertical play which may not seal the manifold too well. I've started filing down the part where the fuel rail bolts on to the manifold so that it can clamp the injectors tighter and prevent air leaks. Just changing out to OEM o-rings improved the car's boost spool. I can't wait for it to be completely sealed and hopefully my vacuum/boost leak will be gone (as that's the only area that is leaking right now)

[nelsonmxmarc]

Maf could just be finished due to normal
use.. Sometimes the thermister goes; rare but it happens! Swap one out or both if you can get them cheap or can borrow a couple to at least verify.

[archenemy236]

I have purchased a new MAFs just waiting for shipping I will post with results.

[Paradis]

I'd chime in with another gratuitous Standalone remark but, oh wait... i just did.

[archenemy236]

Got the new MAFS and installed it the code is now gone but its still running lean, also replaced the FPR cuz i had fuel in the engine oil, now the car is running a 14.8-15.6 at cruise but now under WOT its not moving richest it runs is a 13....like wtf im completely confused.

[CamJohns122]

All your injectors running properly? thats very odd, what management are you running or is it stock ecu?

a little tuning would solve that right up. or if you an adjustable fuel pressure regulator see what its running at?

[Skym]

It shouldn't be lean with intake, exhaust mods. It should be fairly rich, not lean if everything is running ok.

Check fuelpressure at idle and when fuelpump has primed before starting engine. Also, if you have access to a dyno, check fuelpressure on a dyno while car is accelerating. Fuelpump or fuelpump voltage regulator could be the cause of low fuel pressure.

Also check for intake manifold leaks, as RB26, RB25, RB20 are known to blow intake gasket's and get a lean A/F ratio, rough running engine.

[archenemy236]

Im using the Stock ECU it does have a Apexi sticker on it so I popped it open and the board looks untouched...the car also runs well but the numbers aint to good, as i was driving it home last night from the shop it started doing the same old thing 16-17 cruise with a sputter and at idle it drops to a 15.8-16.6, Im about to test the fuel pressure and see whats going on..there is also still signs of gasoline in the engine oil...

[Skym]

Worn piston rings could explain the fuel in oil. Lean A/F ratio could = bye bye pistons rings or headgasket. Dry, then wet (to test seal of piston rings) should tell you what's going on. Sometimes you get a rare ECU that leans out A/F ratio and takes out a cylinder.

[archenemy236]

We checked out the tops of the pistons and ran a compression test my number are all 155-160 and the tops of the pistons look fine...also all of the spark plugs look identical white tipped...

[archenemy236]

now that ive thought about it a little bit more...I set up a Hallman boost controller in the cockpit of the car, it started acting up as soon as I tried to run more boost, anyone think this could have anything to do with it? Also is there a chance that it could be the Boost Pressure Solenoid?