Jump to content
SAU Community

Recommended Posts

i have a autometer air/fuel ratio gauge in my car and i know most people say that they aren't accurate but anyway... i have noticed that when i am driving on the highway in 5th gear and floor it, the car will accelerate but then when it gets to about 4 or 4500rpm the gauge will go from 3 green bars ( rich ) to the last red led's on the other side ( lean ). i pulled out no.6 plug and it was alittle white not alot and i have had those plugs in there for about 3 months or so.

i have a walbro ( *spelling ) 500hp intank pump and a Apexi BOV.. most people with this kind of mods are running rich as hell.

also the car will backfire sometimes.

its a RB20DET 4WD so if anyone has any idea's that would be great..

other mods are 3" turbo back exhaust, pod with CAI and thats about it.

Thanks guys :P

Link to comment
https://www.sau.com.au/forums/topic/41401-am-i-running-lean-or-not/
Share on other sites

Impossible to say until you know whether you have a problem and what the problem is.

You should be more worried about the potential of running it too lean for too long and melting an important engine part, which will end up costing you a couple of grand to fix rather than a couple of hundred. If they try and sell you a new aftermarket ECU that's one thing, but if your fuel pump or an injector is on the way out then you should definitely replace it.

air/fuel gauges are accurate to the extent that they can show you an indication of "rich" vs "lean". that's only richer than stoichiometric though, just because it says rich doesn't mean your fuel ratio under load is correct because stoich is 14.7:1 and you really want to be running somewhere in the region of 12:1 under WOT... BUT, if you give it a bootful and it goes rich and then comes back to lean again then stop booting it, and get it checked ASAP. If the meter is reading correctly and it's running that lean under load then you have problems!

Best case the meter is wrong. Worst case something needs fixing, get it dyno'd and checked and then you'll know.

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


  • Similar Content

  • Latest Posts

    • Ok thanks..that was my second question if i can somehow bypass this even with Nistune(that is all i have right now...aparat from stock ECU. So with some aftemarket it can by "bypassed" or make it work?  I know there is Link or Haltech (mainly used). We have ECUmaster here so i will gather some info about it.
    • Yes. You will need to get the original boost sensor and wire it in. That is.... if you plan to use a stock ECU - even a Nistuned ECU. The Nissan ECU will not operate correctly without it connected. And yes, it will do annoying stuff like you are experiencing. You will almost certainly be better off with some aftermarket ECU, than trying to hunt down rare sensors.
    • Ok so ABS/TCS is "not" the problem. Yeah i know now about the ABS with Nistune(i told that to the Nistune guy) but iam not 100% why or why i dont have ABS. ABS cube is in the engine (always has been) but i had braked couple of times rly hard and brakes just locked and scream. Does all Skylines have ABS cube? That boost sensor https://www.sau.com.au/forums/topic/367633-wtb-r34-gtt-turbo-pressure-sensor-pics-inside/ Is this it? I need to ask but i have a picture of engine bay and i do not see that (100% is not in that place) If i do not have this the car can do what mine is?(cutting around 4000 rpm) Here is the pic of my engine bay(only one i have) BUT i think i dont have that cuz loom was used from my RB20DE NEO and i know (obviously) that it does not have boost control or any wire to that...) so maybe that is the problem? (i dont know for 100% if that car where the engine is from had that)...but i dont have the loom from that
    • I'm with you here. It's either loom has an issue, OR, injectors are not functioning properly. It could even be they're just constantly dribbling, hence the wet, but not firing.
    • Depending on how long the car sat it is very possible for injectors to be stuck open or closed, I'd get them cleaned and flow tested. Other than that, obviously when the loom changes and the car doesn't start any more....the loom is suspect so some tracing / comparing may be required
×
×
  • Create New...