PDA

View Full Version : its a lean machine !

HadeS_73
07-17-2005, 11:13 PM
So here what's wrong and what I did :

I got a 240SX with a red top in it,frount mount,boost controler and 10lbs of pressure .Like the car but not impress with the power , its smooth but feels like 170-180 HP . I install a Air fuel meter on it and its reading lean I mean way lean . I turn'd it back too 8lbs and I'm still way to lean . So I start for bad wires . got the wiring diagrams of this sites and some FSM that don't quite match and found I got ground and also got signal to ecu , but positive is at 0.2 too 0.32 Volt and signal is the same . so first question is what kind of signal should I get ? then I kept looking and true some of your post I found that I got a o2 from NX2000 , so I took it off and put a 87 300zx turbo , nothing change . I then started to think I was lean for real so I install a greddy Emanage with only fuel mixture controle , Thing got worse even at zero on all pots . I took it off . I did a ecu trouble code , got #55 no sensor fault . I than wanted to really find complete continuity on the o2 positive wires but it lead to the E.A.I selenoids which I have no Idea where or what it is...

Soooo...
I need to know the where what of that E.A.I and diag prosedure for the O2 especially voltage feed and signal . Or of course if you know what wrong...Please no stupid or bullshit answer . I did my home work and prune this site for hours before posting .

Great sites there is a wealth of tec info here !!
LigouriRd
07-18-2005, 10:32 AM
i'm assuming that whatever A/F meter you installed is reading off of the factory oxygen sensor. The factory sensor is a narrow band and horribly inaccurate when it comes to reading your A/F ratio. What were you doing when you were getting this lean reading, crusing possibly sitting at idle. At either of these conditions the stock o2 is making the engine run at close to Stoichiometric ratio ~15 A/F. This may be too lean for acceleration but it is just fine for cruise and idle. If you want to really know your A/F ratio, invest in a wideband sensor.
g2ic02
07-18-2005, 03:12 PM
your values seem to be correct. On your stock narrow band I believe they read values from .01v-1v , You really can't accurately read from those numbers. If you want to know your a/f they make a large range of widebands as Ligourird stated. (lm1 and plx seem to be the best ones) bnecustoms.com sells them.

As far as your h.p. is concerned. I dyno'd at 189rwhp/175 tq @ 8 psi . So your butt dyno isn't all that far off.
HadeS_73
07-18-2005, 07:00 PM
It did cross my mind that it could be a wideband thing ( which I knew existed on a certain planet but did'nt know what it was) The A/F meter is a autometer superlight .I guest it will have to plug it on another toy ...

Anything on this E.A.I. selenoid ?
g2ic02
07-19-2005, 09:41 AM
sorry man not sure what the e.a.i. selenoid is. Maybe some one could answer that question. Or if you rephrase what you mean by the question i may be able to help.
Modern
07-19-2005, 10:48 PM
It did cross my mind that it could be a wideband thing ( which I knew existed on a certain planet but did'nt know what it was) The A/F meter is a autometer superlight .I guest it will have to plug it on another toy ...

Anything on this E.A.I. selenoid ?

there is your problem
HadeS_73
07-20-2005, 10:01 AM
yeah, the A/F meter problem will be solve tomorow I will just hook up to the exhaust a second O2 sensor that run a normal reading and hook up the autometer to it .


the E.A.I. selenoids : O2 sensor as 3 wires , negative goes to ground, signal to pin 102 on eccs and positive goes to pin 1 of the E.A.i. selenoid...

also I still have to figure why the Emanage was not working before I install the new fuel pump and injectors.

Thanks for the wideband info its my biggest break in a week !
DeatschWerks
07-20-2005, 10:02 AM
your O2 sensor does not control your afrs under load (open loop). Since you aren't throwing any codes and your car is running smoothly, I wouldn't waste much time trouble shooting for a problem that probably isn't there. Do you have a stock exhaust? If so, this can be a HUGE bottleneck. Throw on a 3" turbo back exhaust and you will probably see a big difference.

stock SR's just aren't all that fast.
sdtouge
07-20-2005, 12:38 PM
stock fuel pump?
Rezlo
07-20-2005, 01:04 PM
your O2 sensor does not control your afrs under load (open loop). Since you aren't throwing any codes and your car is running smoothly, I wouldn't waste much time trouble shooting for a problem that probably isn't there. Do you have a stock exhaust? If so, this can be a HUGE bottleneck. Throw on a 3" turbo back exhaust and you will probably see a big difference.

stock SR's just aren't all that fast.

Ahh the man himself, i tell you if you ever need injectors go to this guy, he REALY does a good job, I got into a friendly argument with a local about how his Tomei Injectors were so much better than my reworked ones, we put them on a flow bench, turnes out my DeatschWerks have a better spray paturn, and are more closely matched than his at like 1/2 the price!

And yes it sounds like you have no problems, I would recomend getting the PLX wideband, its cheap and pretty damm acurate, coupled with a turbo back and some sort of fuel controler it realy works nice,