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Srjustin
01-28-2012, 06:18 PM
Hey i have a sr20det in a s13. I got a harness that has no spot for a o2 sensor? How can i add one? Do i need it? And the car idles high on a cold start could that be why? I need help plz i dnt wanna drive it till i know if its good or bad

AdrenalineS14
01-28-2012, 08:49 PM
And the car idles high on a cold start could that be why?

Does the idle stay high after letting it idle for about a good 10-15mins??? how high does it idle??? High idle on cold start is normal, normally expect either a good 5-10mins around summer time and 10-15mins(actually depends how cold it is outside) around winter time to fully warm up the motor then it should fall to normal around 800rpms or so and stay there at idle.

e5s4y
01-28-2012, 08:52 PM
doesnt have a spot?
i guess find the spot on the ecu pinouts for the o2 sensor and run your own wires? gotta wait for someone with more knowledge to pipe in

iBlaze240
01-28-2012, 08:52 PM
Someone correct me if I'm wrong, but I'm pretty sure every car requires an O2 sensor or sensors. I know my KA has one O2 so you should definitely have at least one. You should probably shop around for a new harness and check to see if it has the missing plug your looking for.

Srjustin
01-28-2012, 09:06 PM
Yesldnt find any spots and i really need someone to point out the ecu spots. Also i only have the car on a short time i just finished the swap. And i have checked everywhere for the o2 sensor it makes no sence to me:/

e5s4y
01-28-2012, 10:04 PM
Just search for ecu pinout sr20det
And there's no sensor in ur elbow? Just an empty hole where it should be? Weird

Srjustin
01-28-2012, 10:27 PM
No i have the senor in the elbow but not from the harness

DaveAZ
01-29-2012, 07:41 AM
You most likely have the harness, but it got lost somewhere. I can't imagine someone cutting it during the swap. Yes, you do need the O2 sensor. It tells the computer if you're rich or lean.

Like people are saying above, you need to find your ECU pins that goes to the sensor. It's three wires on these cars. The correct connectors can be found from Nissan for the 300ZX TT. In our case, we installed a large diameter 300ZX O2 sensor in the aftermarket exhaust and replaced the connector on the chassis harness. The harness on our car went in front of the firewall, then down to where it goes into the interior on the right hand side to the ECU.

Note the O2 connector is the same one that is used on the SR injectors. (at least ours were)

Edit Added: Looking at the 180SX FSM, pin 19 on the ECU is where the sensor wire (signal) goes. The other two wires for the sensor are for the heater, one is ignition power, the other constant ground. The heater power and ground with a few other engine components. Before I started splicing in a new signal wire, I'd unwrap my existing harness and find that sucker.

89JDM240sx
01-29-2012, 07:51 AM
I've heard about using the Z32 O2... I prefer widebands though and you mostly do have the harness for it probably just mis placed it somewhere in there

Srjustin
01-29-2012, 02:33 PM
Thanx for all the help ! Now i had a friend wire one in he found the spot on the ecu. Now how can i tell if it works? Will i throw a code? How do i check codes?

Srjustin
01-29-2012, 03:55 PM
Also would only the wite from the ecu matter? Becuase one is power the other is ground so as long as the ecu wire is in the right spot is should be fine i i have a ground and a power correct ?

89JDM240sx
01-29-2012, 04:19 PM
Get a air/fuel gauge

Srjustin
01-29-2012, 04:27 PM
Idk ii can becuase he wired the o2 in and idk if he did it right thats why i need pics of the wires an asking bout the colors for somreason the harness i had has no o2 sensor

KiLLeR2001
01-29-2012, 06:16 PM
SR20DET Swap Engine Harness Wiring Diagram Guide SR SR20 (http://www.frsport.com/SR20DET-Swap-Engine-Harness-Wiring-Diagram-Guide-SR-SR20_t_26.html)

The connector has three wires:
Brown with yellow stripe, white, and brown.

Srjustin
01-29-2012, 06:47 PM
Thanx i founthat diagram thoe and mines diffrent but. The way he explains it i wired it right aaa i guess ina just buy a new harness thanx for the help guys!!