nger side Running wires through the passenger side of the firewall?

Jan 30, 2004
I'm in the middle of duing my Innovative wideband install and would like to run the wires from the 02 (mounted after the first bend in the DP) through the passenger side of the firewall instead of the typical spot on the driverside. I noticed the main engine wiring harness and antenea wire runs down between the AC box and the fender, is there a way I can pull the wires through there? Any other locations around the AC box?


Doug D
If you want to route the wires through the factory ECM grommet hole, you will need to unbolt and pull back the inner fender/splash moulding to reveal the grommet hole. I'm not so sure that the plug on the harness will fit through that same hole. You might have to cut and splice the harness, which might possibly degrade the signal strength. The other option, would be to use a hole drill that is just big enough to fit the harness connector through then use a rubber grommet and silicone up the hole after it's all said and done. I like putting new holes as close to the factory holes as possible and as far away from hot exhaust components as possible. Other than those two factory holes, I don't know of any others in that general area.
Hope this helps a little.

Pulling away the inner fender and unbolting the harness bracket at the firewall is a time-consuming task to say the least. My sensor is located just before the testpipe, so I just drilled a hole in the trans hump and pulled the wire through there.
if you still have the a/c in your car its going to be a real PITA. you can do it its just going to take sometime.
on the LC-1 the main body doesn't need to be in the car

installed my lc-1 sensor by last bend before test pipe , ran wire from it across trans pan to the LC-1 unit mounted on the brake prop valve and then ran the cables through the factory speedo grommet (could also use the cruise grommet)

have seen it installed incar with the sensor wire run through a hole made in floor by passenger seat and lc-1 unit installed under carpet

for your location i would route the WB sensor wire following main harness put the lc-1 unit under the coilpack and run cables through speedo grommet ,

for lm-1 the cable is longer and you could run the serial cable through the shifter cable grommet
for your location i would route the WB sensor wire following main harness put the lc-1 unit under the coilpack and run cables through speedo grommet ,

That's the thing, I don't think I'll have enough wire to go from the sensor, over the driverside, and back to the passenger side where the ECM is. I planned on leaving the LC-1 box next the blower motor and keep the wiring all on the passenger side.

I'm going to attempt to pull the inner fender well out tonight and see if I can follow the harness through the firewall.

Thanks guys,

Doug D
run it as i said ,should be plenty of wire for the the cable and serial plugs come in at speedo grommet into the car makes it much easier to connect power and heater ground and if you dont have the XD-1 gauge to do the momentary switch and led (i usually put them on the underside of the pillar boost gauge pod) , as for reaching the ecm all you need to do is run two wires from there to the ecm for analog ground and WB analog output #2 , not too dificult just drop the glove box down and push two wires behind radio toward steering column , make the connections to the cable and then with other end to your ecm
with xd-1 gauge theres a short extension provided so having the cable come in at the speedo grommet will help there too , not sure you could reach it if the wires came in at the ecm side ,besides the serial cable you will need to run power and ground for that gauge.
and you wont need the led or momentary switch with the xd-1 gauge , the gauge is awesome and displays the heatup counter and whe in calmode and also for any system codes , and having the display in veiw is great , i have my xd-1 mounted to a flat bracket and slid that between the gauge surround above the radio pod (where most people put their tach)

you should also be able to put the plug for computer connection so it sticks out from the hush panel by the steering column plate so its easy to get to or even sneakeir put it under the console gauge pod if you have one
Try running the wire through the boot around the wires going from the passanger door to the main body. Comes out right next to the computer.