So its a D16a vtec motor from japan--has a p28 converted to obd1 (not by me). Overall my motor is running poorly i dunno why i checked most of the culprits and the motor only has like 65k on it...anyways im not getting any voltage from my 4 02 signal wires...i followed them and they go right into my ecu--also my cel has been on like forever i assumed it was the o2 sensor that was doing it, however, when i tired to jumper the ecu (solid cel) nothing happens no flashing at all or anything. Any ideas?

 

Try switching the two black wires on the O2.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 91SiZ6 &raquo;</TD></TR><TR><TD CLASS="quote">Try switching the two black wires on the O2.</TD></TR></TABLE>

 

hmm im not quite sure what you mean..the 4 wires that go into my ecu are orange brown purple and gray i think--when i start up my engine if those wires are exposed and i probe them with a voltmeter i get no voltage--if that helps..are you saying that i switch the 2 blacks around?

 

Yes, switch the two blacks around. Or rather, the two wires that go to the two black wires on the O2 assembly wiring. De-pin the plug and switch the wires. No guarantee this'll fix your problem, but it's a good place to start. It's the most common problem with the O2 on an OBDI conversion. The wires are the same color, for some lame reason or another, so you either hit or miss the first time.

 

so switch them around at the ecu? Thanks! Ill try it! oh btw is there any trick to de-pinning?

 

oh wait i forgot to say...theres no plug at the connection...i just hard wired them so i tried switching the black wires around---but if you meant at the ecu i will give it a shot

 

hm didnt work--any other ideas?

 

converted not by you ? was the car already converted when you bought it? and what do you mean running poorly? symptoms, I run a d16z6 p28 get some pics in here

 

well--it had some idle issues, plus it just runs pretty rough when it idles around like 700. Perhaps thats just the fact that its got no o2 sensor.. When I bought the car the guy converted it to obd1 and did everything right so ive heard--i tracked down his conversations thru hondatech haha and he got good advice. And i have the rywire 4 wire o2 harness bc i beleive the rywire guys confirmed that the yellow purple gray brown is their harness. So you would think this would work yanno..but nope no voltage whatsoever and a solid cel. ill try and get some pics if it would help

 

when you say solid cel i am going to assume that you grounded out the cel pin and it didnt blink. have you tried running a constant power source to the o2 to bypass the ecu?

 

yea i jumpered it..and it was still solid--what does that mean? No I havent tried the alt power source--what would be the point of that? to see if that clears the cel? I actually dont even know how i would go about doing that haha

 

if there is an issue as far as i know it should be throwing a code. unless your ecu is busted and/or you have a short somewhere. when you say you checked the voltage on the o2 do you mean you tapped into that wire or did you disconnect it from the circut.

 

i just sorta wrapped the bare wires around eachother and probed that connection--got nothing so then i disconnected the o2 sensor and just probed the wires coming from the ecu with a voltmeter (while the car was on of course) If my ecu is bad wouldnt my car like essentially not run?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 91SiZ6 &raquo;</TD></TR><TR><TD CLASS="quote">Try switching the two black wires on the O2.</TD></TR></TABLE>

lol, thats not going to change anything

think of this as a loop, dosent matter which way, same both ways...

 

take these pinouts

p30_obd1
A1 BRN INJ1 INJ1
A2 YEL INJ4 INJ4
A3 RED INJ2 INJ2
A4 ORN/WHT VTS VTEC solenoid
A5 LT BLU INJ3 INJ3
A6 ORN/BLK PO2SHTC O2 sensor (heating element)
A7 GRN/YEL FLR1 fuel pump
A8 (empty)
A9 GRN/WHT IACV IAC valve
A10 (empty)
A11 (empty)
A12 YEL/GRN FANC Fan Output
A13 GRN/ORN MIL MIL (check engine light)
A14 (empty)
A15 BLK/RED ACC (a/c compressor clutch)
A16 WHT/YEL ALT C alternator
A17
A18 (empty)
A19 (a/t trans only)
A20 RED PCS EVAP purge control solenoid
A21 RED/GRN ICM ICM
A22 (empty)
A23 BLK PG1 ground
A24 BLK PG2 ground
A25 YEL/BLK IGP2 to main relay and to gound for o
A26 BRN/BLK LG1 gound
B1 YEL/BLK IGP2 to pin A25
B2 BRN/BLK LG2 ground to shields for CYP & TDC
B3 (a/t trans only)
B4 (a/t trans only)
B5 BLU/RED ACS a/c switch
B6 (empty)
B7 (a/t trans only)
B8 BRN/RED PSPSW PSP switch
B9 BLU/WHT clutch interlock switch
B10 YEL/BLU VSS vehicle speed sensor
B11 ORN CYP P CYP -P
B12 WHT CYP M CYP -M
B13 ORN/BLU TDC P TDC -P
B14 WHT/BLU TDC M TDC -M
B15 BLU/GRN CKP P CKP -P
B16 BLU/YEL CKP M CKP -M
D1 WHT/BLU VBU Back Up Power
D2 GRN/WHT BKSW brake switch
D3 KS Knock Sensor
D4 BRN SCS service check connector
D5 (empty)
D6 ORN/BLU VTM VTEC pressure switch
D7 LT BLU TXD/RXD (data link connector)
D8 (empty)
D9 PNK ALT F alternator
D10 GRN/RED ELD electric load detector
D11 RED/BLU TPS TPS Signal
D12 YEL/GRN
D13 RED/WHT ECT ECT sensor
D14 WHT PHO2S O2 sensor
D15 RED/YEL IAT IAT sensor
D16 WHT/YEL VREF VREF
D17 WHT MAP Map Signal
D18 (a/t trans only)
D19 YEL/GRN VCC1 MAP 5V
D20 YEL/WHT VCC2 TPS 5V
D21 GRN/BLU SG1 MAP GND
D22 GRN/WHT SG2 TPS GND

and wire up the o2 again. i could come out and look at it. i am from west chester. i also run a p28 so we could swap them and see if its your ecu.

 

ah ok so ill make sure that my harness is in the right spot on my ecu? West chester is like an hour away man--haha ill come to you if you want--first i gotta figure out if my ecu is just junk or not--this situation with my cel is what puzzles me though

 

bump

 

BUMP!! did you fix it?

 

bump

 

nope not yet--i figured im just going to have to swap ecus...now im just saving money up

 

so i put a new p28 in there and the problem is the same--I think I have a short somewhere in the wiring but am not sure where to start looking

 

Well, if you continuity check the wires from the O2 sensor, to their corresponding positions at the ECU and each wire is good... then your wiring is fine.
Please do a google search for "how to check continuity" and get a volt meter.
You do not check for voltage (12v+) on each wire, only 2 will give you that with the key in the on position.

step 1. figure out how to continuity check.
Get to it.