B18B

So the car only has 1 o2 sensor (4 wire) that is in the Exhaust Pipe A before the CAT

Instructions states ... if replacing factory sensor ... the only wire needing to be connected to the factory plug .. is the Green wire which sends the signal back to the ECU... so ok ... i cut the 4 wires going to the OEM o2 sensor take it out ... put the new Greddy O2 sensor in .... connect it to the Greddy wiring harness... that leads inside the cab to the control unit .... now... on the greddy harness there is only 1 Green wire ready to connect to the factory wire that sends the signal back to the ECU ... i connected that wire .. to the 1 green wire that was in the factory plug ... the other 3 remaining wires are not used .. i just electrical taped the end .. and slid the little cloth heat slip thing back over it ... now i throw CEL 41 meaning the Heated Oxygen Sensor Heater Circuit has a problem ..

well out of the 4 oem wires .. 2 wires are for the Sensor Terminals (1 of those wires is the green one i tapped into) and 2 wires are for the Heater terminals ... now the Heater terminal wires are no longer connected to anything ... but im not really sure what to do .... those wires no longer being connected going to indefiantely give me the CEL 41 ? and how do i remedy if so ?

 

I messed around with that for quite some time on my '96 GSR. Honestly I think the only way to make that stupid computer happy is to not take it's toys away. IOW punch another hole and drop the Greddy sensor in it. Drill a hole somwhere in your exhaust stream(the closer to the exhaust ports the better), weld a nut that fits the O2 sensors onto it then drop that thing in there. You'll be fighting with it all year otherwise I suspect.

 

i suspected the oem o2 sensor (130k) was faulty... so i replaced it with the new greddy sensor when i got the gauge... id drather aviod connecting another sensor back up .... i was more along the lines thinking of connecting some kind of little resister or something

thanks tim any other suggestions ?

 

Well you can test the OEM sensor with an ohmeter. It should be around 14 ohms across the heater circuit. I believe the Greddy sensor only has a resistance of about 7 ohms, so if you have that spliced to your OEM sensor socket, I would disconnect it immediately as it will pass 2x the current and stands a good chance of blowing a chip in your ECU. Trust me I know. If you'd like to figure out the value of the resistor required to run the Greddy unit safely I'll try to help, but I'm telling you I played with all of this on my stock OBDIIa ECU(P72) and though I eventually got it to work fine without throwing a code(02 sensor simulator) I now have a blown Sanken chip in my ECU. The chip is tied directly to the secondary O2 sensor's heater circuit(code 41). I've spent 2 weeks locating a new chip in quantities of less than 500 and cannot. Partially because the chip (STA335A) is no longer in production, and partially because there seem to be none in this country and importing them from Japan is expensive. Additionally Sanken was aquired by Allegro micro a few years back and that is NOT helping.

I strongly advise you to get a cat for an OBDII car(with 2 bungs) or punch another one yourself. The Greddy A/F is a fine unit, but it's not worth risking your ECU when there's a simple solution...especially with your OBDI setup.

 

Can i just hook the 2 Heater Circuit wires, ONLY, back up to the original O2 Sensor ... and just zippie tie it to the, open air, underbody somewhere LOL something i can rap it in so it cant get wet ? and ill zippie it to the power steering rack or some **** LOL (;

 

This is the kind of thing allot of people do, though mostly with the secondary sensor on an OBDII+ car. I did that with mine and it was fine for awhile then throws codes for improper O2 sensor readings. Then I tried different resistor values with varying success, followed by a sensor simulator. I told you the only 100% sure way I know to get the Greddy working and keep your car's computer happy. You may have some luck because you're not hindered with this OBDII blessing though.

 

[QUOTE]This is the kind of thing allot of people do, though mostly with the secondary sensor on an OBDII+ car. I did that with mine and it was fine for awhile then throws codes for improper O2 sensor readings. QUOTE]


Hmmm well connecting the Heater Circuit wires up ONLY... wouldnt it just keep the O2 sensor warmed up ? the Sensor wire, from the OEM o2 wiring plug, is connected to the New Greddy O2 ... so the correct values should be getting reported back to the ECU

anything wrong with just trying what i mentioned? sounds like the cheapest and safest way to me (;

 

It's the cheapest anyway. Give it a shot, the only thing is that the Greddy may well not report the same voltages as the stock sensor. I know mine did not as a stand in replacement for the secondary sensor. I rigged wires across the +/- of the signal wires on the stock and greddy O2 sensors for comparison purposes.The Greddy would cause the computer to believe my car was lean, and richen the mixture. Lemme know how it comes out. I have an OBDI ECU on the way, so basically I'll have the same situation you have now. I already have an OBDII cat though and will be punching a hole in the resonated test pipe I have soon.

 

Ill keep you posted boss ... can you tell me a little about your Greddy A/F calibration setup deal ... like i have everything connected and the needle fluxates ... i did the break in that the instructions stated on the sensor ... but im reading maxed out rich 8.0 and ill let off the gas and decelerate and it will go to the extream lean 18.0 or whatever is on the gauge there ...

just curious what all you had to do to get it to read correctly .. and what your present readings are at idle ... partial throttle and wide open

it would really help me out .. thanks man

 

I used the Greddy exclusively to set my Vafc. I aimed for a target of about 13.8 across most of the RPM range. The exception being higher RPMs w/ wide throttle. I aimed for about 13:1 here. It always runs lean at idle. My idle with the Crower's was icky at the best gear setting of +2.5I/+.5E, and when I got the A/F setup I cut the fuel at 1k by about 20%. This resulted in the gauge reading about 10.5:1ish. It smoothed the idle out considerably. The way it swings to max lean when you clutch is normal.

BTW when I was done setting the Vafc up with the Greddy I eventually got the car to a dyno with wideband and the numbers matched almost perfectly. I was rather impressed with the Greddy unit.

 

Sweet i plan on using it to help set my SAFC .. but when you plugged everything up ... did the needle pretty much read accurately ? or did you have to configure it in any way with the little control model thing ?

 

https://honda-tech.com/zerothread?id=134260

 

Good thread Dee.

Yeah it was accurate without any adjustments on my setup.

 

no problemo!

 

thanks dee im gonna give it a try on my day off ... thanks for the info.... tim thanks for your help too...

i think i have the green greddy wire connected to the green wire on the honda connector ... ssoo i dunno... maybe the ride isnt seeing a o2 sensor at all at the moment .. would that in turn cause the ECU to run the car rich ? hence me getting the 9.0->8.0 on the gauge while driving ?

 

dayum man. I'm confused on the wiring myself. Although I do plan on placing a separate bung to utilize the provided GReddy O2 sensor. Now If I use the GReddy O2 sensor, will I still have to wire the GREEN wire (located beside the big black connector) and the RED wire (located beside the 2 clips besdie the data link module)? Please help......


Modified by thermalfi'd16 at 10:34 PM 12/31/2003