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Forum nameTurbo/Nitrous Tech
Topic subjectRich or lean? What the hell is going on?
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i8&topic_id=78601
78601, Rich or lean? What the hell is going on?
Posted by Dirty, Oct-25-04 11:44 AM

Here's the deal. No matter what I do with my sfmu, I keep getting lean readings from my AF gauge. My readings are usually between maybe .97 to .84. As the rpm increases and as the gears shift higher it gets leaner.

Now this is what gets me. My EGT's don't get too high while atWOT running .84 and I pulled my plugs today and they don't show signs of running lean. In fact, it looks more like richness than lean. I'm idling @ 30psi and @ WOT my fuel pressure is around 80psi with my 30# inj.

Could my AF gauges be fucking with me or does this sound like I'm still fooked?
78602, RE: Rich or lean? What the hell is going on?
Posted by siueclipse, Oct-25-04 11:52 AM
get a wideband.
78609, RE: Rich or lean? What the hell is going on?
Posted by Dirty, Oct-25-04 01:35 PM
Ummm. OK. Whenever my blue collar job gives me that 30 cents raise I'll go right out and get 2 of those.
78612, RE: Rich or lean? What the hell is going on?
Posted by dsmtuner, Oct-25-04 02:48 PM
my wideband does the same thing though. it reads lean all the time but the egt dont get too high and there are no other signs of running lean.
78618, RE: Rich or lean? What the hell is going on?
Posted by Ducking_Fumbass, Oct-25-04 05:06 PM
www.wbo2.com

www.zeitronix.com

Tuning without a wideband is just guessing. You don't want to guess with your motor, do you?

I mean, which is more expensive, 280 bux, or 2800 bux, or whatever it would cost to build the motor again?

From where I stand, you can't afford to NOT use a WB.
78619, RE: Rich or lean? What the hell is going on?
Posted by Dirty, Oct-25-04 05:16 PM
A wideband would be nice. I've got my eye on the zeitronix, but until I can afford to get one, I'm just gonna have to work with what I've got just like everyone here did for years until people started getting the widebands. I'd rob a liqour store but I'm afraid my engine would blow trying to get away. :shrug
78621, RE: Rich or lean? What the hell is going on?
Posted by jsupetran, Oct-25-04 05:52 PM
Hey how about replacing your O2 sensor. I know my car used to get weird a/f readings before getting a new sensor. That maybe it. You can always buy one at oxygensensors.com for 62 shipped or swap O2 sensors real quick just to test it.

Edit; Also, have you considered joining the zeitronix gb? 240 and your set (need crappy laptop).
78624, RE: Rich or lean? What the hell is going on?
Posted by Dirty, Oct-26-04 03:48 AM
The sensor is a new one and I tried another one just in case, but get the same readings.

I'd like to get in on it, but I just bought a house and my pockets are light right now.
78682, RE: Rich or lean? What the hell is going on?
Posted by Dirty, Oct-27-04 11:30 AM
Today I was doing some runs and my AF was 1.03 - .99. Today was pretty warm also. Do you think that the outside temps would have anything to do with my problem. It did start when the weather got cooler. I still don't know what's going on.

I know I need to get some better tuning tools, but right now I just want your guesses to what might be causeing this. I ran for months with great readings and all of the sudden I'm lean.
78684, RE: Rich or lean? What the hell is going on?
Posted by dsmtuner, Oct-27-04 11:36 AM
fuel pump? i was fine for a while then went lean and my mechanic thats been helping me with my builup checked it over and said it was the fuel pump going bad. just a thought. still havent replaced it, i just keep turning fp up.
78689, RE: Rich or lean? What the hell is going on?
Posted by Dirty, Oct-27-04 02:31 PM
My fuel pump is brand new and was put on the car when the turbo was. I've been boosted for maybe 5 months. Thanx for the idea though.