I'm thinking of putting a Air/fuel gauge in my truck as well as other gauges from Autometer. And my Question is does any one know which wire is the signal wire on the Oxygen Sensor that I would have to tap into?
Any help would be great!!

 

on a neon it is the blac wire with a green stripe if you are looking at the o2 sensor and the clip is up it is the first one on the left at the top

but black with a green stripe
98rtsrt4killer
custom srt-4 shifter in a 98 neon
why would you not want that

 

Thanks, I'll try and see if it is the same on the Rams. I doubt Dodge would change too much from model to model.

 

Just curious...any practical use for it? Both of my kids put one in theirs. We all agree it looks cool when running but since you can't do anything about mixture., what's it really doing? Not criticizing, just questioning.

 

The purpose of the air/fuel gauge is to keep an eye on the mixture when your adding boost or juice. If you run it too lean (not enough fuel for the amount of air) you can cause damage by creating too much heat. This is especially important on carbed engines (proper jetting). I have seen holes burned through pistons on some two stroke motors that were fuel starved! With FI systems there are checks and balances to assure that too lean a mixture is not obtained. It does this by adding more fuel via the injector by increasing its pulse width (the time its open) or by retarding the timing (spark knock sensor which has more to do with timing of the big boom). If a lot of boost is added, I'm talking about super/turbochargers, a new set of higher flow injectors and more times than not an auxillary fuel pump is needed. When you look at your kids F/A gauge you will probably notice that it goes rich when they floor it and goes more towards the theoretical optimum of 1 part fuel to 14.7 parts air when they are idling or just let off the gas. In a FI engine it typically uses the MAF, TPS, O2 sensors to complete this "basic loop". Example TPS senses you just floored it, Pulse width will increase because it knows it is going to get a rush of air very soon, MAF tells it how much air is coming in. After the cycle the O2 sensor detects if the mixture was lean/rich and adjust accordingly. The MAF/O2 work intricately together and the TPS help smooth things out for daily driving. The TPS also helps control shifting and a few other parameters but you get the basic idea. Hope this helps.

 

You're right.

The funny thing is that since DC is locking down the PCM's on these vehicles so tight, and the IAT's don't compensate for air volume like an MAF, it makes it nothing more than a cool gauge to have on the dash. Unless of course you've dumped a buttload of money into a custom Fuel Management System to run you engine.

 

I completely forgot to mention the IAT! For those who care it does exactly that. The cooler the air is the more oxygen it can hold relative to the elevation. As elevation increases the partial pressure of O2 decreases. Remember Boyle's Law? Anyhow, that is the concept with CAI and the like. For all you racers, you will also post your bewst times when it is dry and cool outside. But I'm just bored and rambling. Hope everyone had a good weekend!

 

Yeah plus it looks cool as well. I'm also putting in Tranny temp and Oil Temp.
I guess, from what I've found out now I have to weld a new bung into the downpipe and put in a single wire O2 sensor for the gauge because the factory O2 sensor runs funny voltage!

 

Can you post a pic or at least describe where you are mounting the gauges. I know of the pillar mounted ones, but I didn't think that 3 would fit. I am personally more interested in the tranny and oil temp gauges.

 

I'll post a pic when I have finished installing the gauges, but I'll describe where I am putting them. Autometer now has a three gauge pod that goes in the centre console and replaces the cubby hole (If you have one) below the heater controls. That's where I'm putting them. The Tranny temp and Oil temp are the most important but I needed a third so I thought the Air/fuel would be a nice touch, even though I can't control it.