Im getting ready to hook up an air/fual gauge and fuel pressure gauge. The air/fuel looks pretty easy, im not sure about the fuel pressure yet. Any tips on where i should tap into wires, for ignition, or anything info that would make this easier for me would be appreciated.

Thanks, Joe

 

For both gauges, you need to tap into a lighting circuit for the gauge lamps. Pick up +12V power from the headlight switch or the panel dimmer rheostat, so the gauge lights only come on when the parking and headlights are on. Lighting ground wire can go to any metal screw or bolt under the dash.

The A/F ratio gauge needs to connect to the harness wiring for the O2 sensors... not to the stainless steel sensor wires. The O2 sensor wires can be found at PCM pins C8 and C20. One is purple, the other is purple/white. You can attach a signal wire to each of these wires, bring them both to a single-pole/double-throw switch, then run to the A/F gauge. That will allow you to monitor either the left or right O2 sensor. Of course there is not a lot of useful info from an A/F gauge, but the psychedlic light show can be enteraining.... .

The fuel pressure gauge should be electronic if you are putting it inside the passenger compartment. The pressure sensor needs to be attached to the Schrader pressure test port. My suggestion... - remove the core from the Schrader valve. Attach an NOS PN 17535 -4AN 90-degree swivel fitting to the Schrader. Then run a 24" s/s braided hose.... -4AN on one end to the NOS fitting, 1/8" NPT on the other end to attach to the pressure sensor. I've seen these hoses on e-Bay for $12. Otherwise, NOS sells them.

Using the hose allows you to get the pressure sensor off the Schrader valve, out from under the cowl, and away from the heat and vibration of the engine. Tuck the sensor away behind the PCM. Run the wires thru the firewall by using the big rubber grommet behind the PCM.

Should get you started....

 

Fred thanks for the info, that will definitely get me started. One question, wheres the Schrader valve located?

 

On the fuel line, behind the intake manifold, easiest seen from the passenger side of the engine. On most of these things, you can't go wrong by looking at Shoebox's Tech Pages.

You can also see it in this picture.... with the NOS part screwed on it.

 

Fred, there may hope yet, for those that insist on purchasing on of those near worthless 'light shows'. If by chance, (I know, highly unlikely) any of these individuals, were to purchase an Innovate LM1 WB controller, it could be programmed to simulate a 0-1 volt NB sensor signal, which can exported to one of these ah, lite shows, rendering them almost useful as far as displaying some useful info. No, it wouldn't convert lites to digits, but...nonetheless. Oh, and yes, this same simulated voltage can be exported to oem pcm, as well. Hmmm.

 

Thanks injuneer i needed that info too!