Real Fiero Tech

I just recently purchased this:

http://www.ngksparkplugs.com//products/ ... country=US

I got 13' of wiring, so that should be more than enough for a clean routing. I would like to hear what some other people did to wire up their widebands. Also, where did you splice in the get power to it? I'd like to hear some ideas to help me along in the wiring process.

Thanks!

I have an LC1. Its mounted inside the trunk, and i have an area that the cable runs through. Coming out of the LC1 is a sleeved harness that runs along the driverside of the engine bay, into the cabin. I grounded one of the grounds to the 7mm where the pcm grounds, and the other to a 10mm bolt that holds the skeleton. I extended the power wire to the fuse box, but you can get power from the C203 just as easily. My analog outs are pinned to the ECM and the other to my AutoProm.

I pulled power from my cig lighter and installed a switch. Gives me the option to have it off if I want.

Mine is a plx mounted above the tach on the dash

That dosent look too hard to make, what is the output range and resolution of the WBO2 sensor. All you would have to do is average that signal, and display it. Sounds like a fun project. Did whipped already do this and much more with a dash display using obd2?

Shaun41178(2) wrote:I pulled power from my cig lighter and installed a switch. Gives me the option to have it off if I want.

Mine is a plx mounted above the tach on the dash

Interesting....... That's something to consider. I plan on mounting mine in the same spot. I have my scantool mounted in a pod off the side of the dash by the trunk release, so to view it and the wideband will be easier.

Us obd2 guys run it through our EGR.

God wrote:I just recently purchased this:

http://www.ngksparkplugs.com//products/ ... country=US

I got 13' of wiring, so that should be more than enough for a clean routing. I would like to hear what some other people did to wire up their widebands. Also, where did you splice in the get power to it? I'd like to hear some ideas to help me along in the wiring process.

Thanks!

The AFX needs to be powered up and allowed to fully preheat the WBO2 sensor before you start the engine. You probably already know this assuming you read the instructions included with it.

So what you need to do is wire the power source for this unit up to a switched IGN1 circuit. I would tie/splice it into the IGN B+ pnk/blk wire going thru term F of the C203 connector (this wire also powers up the PCM in your car). If wired up in this way all you need to do is key on the ignition switch, watch the AFX display and wait until it counts down to 0 then you can start the engine.

Concerning routing, there should be some room left in one of those bulkhead grommets I ran some wires thru for your PCM out to the engine. (hole/gromment was originally used for a manual trans shift cable; should be located next to the auto trans shifter cable) You might have to slit it so you can work the wires for the AFX in as well. Or you can drill a new hole and pass the wires thru the firewall but just make sure you use a grommet to protect the insulation on the wires.

Out in the engine compartment just make sure you try to keep the AFX wiring away from the plug wires and exhaust of the engine and you should be ok.

-ryan

I've got a question that has been on my mind Ryan.

I will be running a few accessories on switched ignition power, and all off of basically the same source. To included will be a WBO2 sensor, 2 electric water pumps (Both use relays however), and maybe a set of 3 gauges. Will this cause any problems? Should I find another source other than the ECM power?

Aaron wrote:I've got a question that has been on my mind Ryan.

I will be running a few accessories on switched ignition power, and all off of basically the same source. To included will be a WBO2 sensor, 2 electric water pumps (Both use relays however), and maybe a set of 3 gauges. Will this cause any problems? Should I find another source other than the ECM power?

Funny you should mention that because I have some info about what GM is doing nowadays. But before I get to that...

Basically you can run as many things off of a single circuit as long as you don't overtax the current capacity of the wiring used in that circuit or the fuse you are using. So as long as your water pumps are getting their power from another source thru their relays (and you are only using this ign switched source to power up the relays) I don't see anything wrong with your setup. The stock Fiero ECM IGN circuit can support up to 15amp nominal current; but I think 20amp would be the absolute maximum. As long as you don't exceed this, you should be ok.

Now what I have discovered on this LS4 swap, and looking at the wiring diagrams for newer GM cars; they are starting to use powertrain power supply relays; similar to what chrysler started doing back in the 80's. Basically the ignition switch sends a signal to the BCM/ECM and in turn a signal is sent out from one of those computers to activate a relay that in turn powers up all of the other devices on the engine (such as the various solenoids, injectors, etc). I believe they designed the system this way so they don't have to run all of the load thru the ignition switch in the newer cars; this also keeps the bulk of the heavy gauge wiring in the engine compartment instead of having to run it inside the car to the ign sw. and back out to the engine. The same thing can be done in a Fiero and is actually a good idea.

-ryan

Thanks for the reply. I don't plan on rewiring the car to do that, though it's good to know.

I will be using the switched power to key up both water pump relays, but the WBO2 sensor will not be on a relay. However, if I end up blowing the fuse, then I will relay it and see if that helps.

Thanks again, I'll speak up if I run into any problems.

even if you use relays on your water pumps, you may experiance anomolies with your high tech sensors. Most likely not, but if you experiance problems, you might want to run a dedicated supply and ground.

Someplace in the A-body community is a website on which a guy describes how he rewired his headlights to be run by relays and heavy gauge wire instead of going into the car, through the ignition switch and fuse block and then back out to the headlights. He said there was a visible improvement in the light from his headlights.

Will, yeah, that's exactly what I did on my last custom truck build. You can just assemble the stuff you need yourself or buy a kit like this one from Painless....
http://www.jegs.com/webapp/wcs/stores/s ... 2_44232_-1
Painless makes about 3 different kits for various headlights. On my truck (based on a 1990 Carpice) it made a huge difference. The original wiring for the lights on that car was some really thin guage stuff.