Jump to content
SAU Community

M35 Lean Now Not Lean Strange Codes

zelda

By zelda,
in Four Door Family & Wagoneers

 Share

Recommended Posts

zelda Enthusiast

zelda

Posted
Posted

Hey everyone,

Having some issues with the stagea i cant quite figure out.

Dont like starting a new topic and iv done some extensive searching on these forums so heres the rundown

Car has HDI kit, custom bov pipe ( 3inch from kit ) kompact bov, changed vac hoses except one with restrictor going to WG actuator, boost solenoid blocked off so should be running on wg pressure, scottys dump pipe and a walbro 255 not yet on 12v constant.

Somewhere along the line it threw a lean code on bank 1 P0171, i had the fuel pump done along with filter etc thinking this might clear it but to no avail, however the car still idle fine just bleeds off boost around 9psi according to the tyrbosmart guage not the usual 12ish it used to even after ditching the solenoid.

So i dropped it off to a reputable auto lekky and had him throw the scanner on it and run some tests, he found a couple of small leaks and while i was there i had the injectors flow tested and serviced for peace of mind.

Got the car back, the code had gone but still bleeding off at 8/9 psi and still rather whiney ( as always ), about a week later the CEL came back and gave me the lean code again along with Electronic throttle control ( guessing TB ) and throttle or pedal pos sensor, assuming they both go hand in hand.

Unfortunately i needed the car for the week and couldnt get it back to them to investigate further

Strangely enough two days later i start the car and now the codes are gone? It feels like its got a little more grunt now too but still bleeding off early!?

Sooo im scratching my head, could the AFM be going? Or the wastegate opening early? Heat is not proving to be a factor with the gate AFAIK, the idle is always 650 once warm, idle inHG is around 18/20 ish as mentioned drives fine untill that 8/9psi mark then just spins no more and is a sluggy sounding whistle really.

Anyone willing to throw in some input is greatly appreciated,

Ps will change the lower rubber pipe before intercooler not supplied with hdi kit to this dolphin hard pipe when it arrives.

Cheers!

Link to comment
https://www.sau.com.au/forums/topic/464324-m35-lean-now-not-lean-strange-codes/
Share on other sites
zelda Enthusiast

zelda

Posted
  • Author
Posted

Check fuel pressure, check manifold for leaks or cracks. Lean code could also be a misfire. Coil packs or plugs.

Checked for leaks, although it wont hurt to do it again, plugs have been done LFR7s iridium if i remember,

Is it worth putting a FPR with a gauge on ? Relatively cheap and harmless to do i would imagine - whats the standard pressure about 44psi ?

Cheers

zelda Enthusiast

zelda

Posted
  • Author
Posted

I haven't checked OEM pressure, I would assume 43.5 psi with the vac line removed. Would be worth checking the spec.

I would also check the Oxygen sensor...is it average on fuel?

I would hope the o2 sensors good as the dump pipe was only put on about a month ago, pretty comfortable my mechanic would of pointed it if it was the case, he did mention it was in a way more sensible place haha, yeah the fuels about right ~ 650km per tank mixed driving

Ill see if i can find the spec for the FPR and give that a go othewise im leaning towards rebuilding the turbo ?

scotty nm35 Grand Master

scotty nm35

Posted
Posted

When you say checked for leaks, did you pressure test the intake at 20psi+? I have seen many leaks that would never be found using a smoke tester or visually, 20 psi into the intake usually sorts them quickly.

The other common issue is the fuel reg hoses, they commonly fall off as there are no barbs. Make sure you cable tie both ends. Checking the reg at base fuel pressure you will need to remove this vac hose.

Other than that, before you start swapping turbo's, have you tested the test device? I have seen more boost gauges fail or reading wrong than wastegate actuator problems.

  • Like 2
zelda Enthusiast

zelda

Posted
  • Author
Posted

When you say checked for leaks, did you pressure test the intake at 20psi+? I have seen many leaks that would never be found using a smoke tester or visually, 20 psi into the intake usually sorts them quickly.

The other common issue is the fuel reg hoses, they commonly fall off as there are no barbs. Make sure you cable tie both ends. Checking the reg at base fuel pressure you will need to remove this vac hose.

Other than that, before you start swapping turbo's, have you tested the test device? I have seen more boost gauges fail or reading wrong than wastegate actuator problems.

I'll have to check with my auto spark, he found the leaks and didnt mention weather it was pressure tested or otherwise,

As for the reg hoses they are tied on and im always checking just in case one does pop off, checking for the base pressure im assuming it can be either one scott?

As for testing the tester, well i still run the factory gauge ( not much to go off i know) as well as the AM one which is a brand new unit, T'd off just before the factory boost gauge sensor, since the problem arose the factory gauge has never hit the same mark ~1bar

I think the next most sensible step is to make a boost leak tester and rule it out for myself, although iv been vigilant in sealing everything and tieing all hoses etc it needs to be seen with my own eyes, and ill let you know how it turns out, any one got any pics of there home made boost tester suited for the stag?

Thanks again!

Zach

datmoo Proficient

datmoo

Posted
Posted

I'll have to check with my auto spark, he found the leaks and didnt mention weather it was pressure tested or otherwise,

As for the reg hoses they are tied on and im always checking just in case one does pop off, checking for the base pressure im assuming it can be either one scott?

As for testing the tester, well i still run the factory gauge ( not much to go off i know) as well as the AM one which is a brand new unit, T'd off just before the factory boost gauge sensor, since the problem arose the factory gauge has never hit the same mark ~1bar

I think the next most sensible step is to make a boost leak tester and rule it out for myself, although iv been vigilant in sealing everything and tieing all hoses etc it needs to be seen with my own eyes, and ill let you know how it turns out, any one got any pics of there home made boost tester suited for the stag?

Thanks again!

Zach

post-135423-0-70541000-1461244457_thumb.jpg

zelda Enthusiast

zelda

Posted
  • Author
Posted

Is there any reason i couldnt pressure test it at the suction pipe and cap off the bov return? I might sound stupid but would this in theory test through the turbo for leaks and save me getting under the car? Just a thought cheers

datmoo Proficient

datmoo

Posted
Posted

Is there any reason i couldnt pressure test it at the suction pipe and cap off the bov return? I might sound stupid but would this in theory test through the turbo for leaks and save me getting under the car? Just a thought cheers

Give it a go. Mine was more to do with pipe size as I already had this made for my Datto.

zelda Enthusiast

zelda

Posted
  • Author
Posted

So still havnt managed to get the boost tester on it yet, but engine light came back on again today after drving open roads for about 150ks

P0171 is back left bank lean

P0120 throttle position switch

P1122 any one got any clues to this one??

Thanks again for your input guys

Zach

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • GTSBoy
      RB20 in need of modest love injection

      By GTSBoy · Posted

      As you're looking at using a Link ECU, then large injectors are not a problem. But there's not really any need to go 1000s on an RB20 unless you're planning >>600HP on E85, which would seem unlikely. There are other options for injectors. The Xspurt ones are available from a number of places and you can get them in the mid 600s and 725cc, which is probably a sensible place to be. These are all EV14 based. If you are not using the stock AFM (at all, which would be the case with a Link) then a large turbo intake pipe to suit the ATR turbos is not an obstacle, so you should use one instead of a highflow. Results will be better.
    • QB6SAGR
      RB20 in need of modest love injection

      By QB6SAGR · Posted

      Hey guys,  I'm after some advice and this here is the best place to get it imo. I was a member a looong time ago under another account, with a lost email address. Its nice to jump back on and see some of the same names still giving good advice.  I mothballed my car when i moved to perth in 2013, and after getting towed across the nullabor a few times it has officially done more km's on a trailer than under its own power. Now that i have started the process of tidying up and modifying it, i see the fruit available (and the fruiterers selling the produce) is different than back in the day. hence my questions, as i used to 'know' what to get and now, i'm not so sure. Engine wise the car (92 gtst) has a walbro 255, k+n, fmic, cam gears and and turbo back 3"exhaust. Wish list is a Hypergear high flow or ATR43G1, Link G4x and some newer injectors before a tune up. My goals are modest, only low 200's power wise. i know i could achieve this with less, but i've been swapping out old for new where i can. Every cooling hose has been replaced, along with mani gaskets, WP, thermostat and radiator, fuel pump and timing belt, tensioner and idler, and i rebuilt the steering rack. Regarding the injectors, the fruiterers all seem to sell what used to be considered quite large injectors. There are a lot of options for bosch 1000cc EV14's, and i would like to know if that is a suitable choice for my build. Is modern injector design good enough to run these at the low duty cycles that i likely would be? is there a downside to running a too large injector these days? or, would there be an upside to running a smaller injector at higher duty cycle? I can see that there are smaller injectors still available, but the ones i have seen specifically marketed for RB's are pretty large (see: https://golebysparts.au/collections/fuel-rail-injector-kits/products/nissan-rb20-fuel-rail-bosch-980cc-1150cc-injectors-turbosmart-fpr800-regulator-kit), and i dont know enough about them to say one not marketed for RB's would fit or not. I have searched the forums, and amongst all the posts on older tech, I did see gtsboy recommend EV14's, but no size was mentioned... again, i'm not clear on if the smaller size bosch injectors are also EV14's as they do look similar.  also, if someone can recommend a tuner familiar with RB's in the Geelong or West Melbourne area i'd appreciate it. Thanks in advance guys. Cheers, Rowdy  
    • Duncan
      R33 GTR lift points for hoist

      By Duncan · Posted

      FWIW the depth of the groove in the rubber pad is not super essential, the blocks are rubber and squish a bit. If you are worried an angle grinder will make a deeper groove quick smart
    • GTSBoy
      R33 GTR lift points for hoist

      By GTSBoy · Posted

      I mean, if you were to move the jacking points away from the original location, that is, away from the wheels and closer to the centreline of the car, then it will be more likely to overbalance and tip off the supports. Same as we talked about before. I was talking about moving for-aft. If the sill is bent outward or inward, then the car would obviously look unstraight from the outside. Hopefully that hasn't happened either. Again, you can do comparative measurements from the chassis rails to see if there is much deflection.
    • sunsetR33
      R33 GTR lift points for hoist

      By sunsetR33 · Posted

      Can you elaborate what you mean with your first sentence? I meant move as in the bulge kinda seemed like it got pulled "outward" meaning it got pulled down and to the side with the jacking rail itself, so the load bearing bulge now sits lower than usual and is not level with the sill on the other side of the jack point. Either that or the jacking rail just got pushed in a good bit.
×
×
  • Create New...