I am looking to buy cable/software for 95Z with the OBDII style connector, but running OBDI. Does anyone know what software would allow me to lean out my A/F? I have Hooker LT with O2s in each collector. I am not lighting up SES either. Not sure if what I am asking is possible, but I would like to try and lean out due to excessive smell and gas prices LOL. Thanks in advance.

 

You really cant lean it out even with a programmer. The computer is hard wired to keep the 14.7:1 AFR during normal driving conditions.. WOT is totally different. There is software and cables available to change parameters in the computer but it wont do what you are wanting. There are ways however youre gonna need a wideband O2 sensor to do it.. basically if you have to ask how its probably not a good idea.

 

I was afraid you'd say that. I know without the cats I am going to smell a little, but it seems excessive. Could I have bad O2s or maybe open/closed loop situation? I certainly don't want to put holes in the pistons (too lean) but not sure if I am running at 14.7:1 A/F either. Is there software that will tell me where my AFR is throughout the power band? If I am at the optimum 14.7:1 at idle and richer going up in revs, then I will put air freshners in the car.

 

If its really bad on a stock motor then you have something else going on. Could be bad O2 sensors or a bad exhaust leak or maybe a ripped intake elbow... several things. Try replacing the O2 sensors if you havent already. If you are into spending money then buy a cable from AKM cables and TTS datamaster to log some of the engine parameters. That will let you know if the computer is adding or subracting fuel... and give you a VERY rough estimate of the AFR.

 

I know on the 3rd gens, turning up the fuel pressure meant a way less gassy smell (exhaust being burned properly)...unfortunately with the 4th gens, they re-learn their fuel pressure by itself. And 4th gens already come with fuel pressure up high.

 

The only thing that helped the smell on my car was to add a little timing at idle/coming off of idle. Then again with my cam, nothing in the world is gonna completely get rid of the unburnt gas due to alot of overlap.

Ryan

 

To lean out your cruising AFR could always run open loop all the time, but that would take some tuning with a wideband O2 (which also answers your question about measuring your AFR). The LM-1 from Innovate Motorsports looks to be a nice offering. You would have to use this in conjunction with reprogramming software from Tunercat or LT1Edit.

 

You could tell your computer you have 25# injectors to lean it out a lil bit...

 

But in closed loop the computer would just learn its way around that and add fuel. Same thing if you alter fuel pressure.