95 Wrangler O2 Sensor Wiring HELP!

I just purchased a 95 Wrangler with the 2.5L 4 Cyl. engine. I get a code

21, which is related to the 02 sensor. The guy I got the jeep from just replaced the 02 sensor. The connector was bad, so he cut it out and spliced the wires together and got mixed up. He said ever since then the light comes on. The engine runs fine, but does not idle well when it heats up, I am hoping this is related to the sensor, but it may not be. I just want to get the light out.

Can anyone tell me how to wire this thing? There are the following wires coming from the wiring harness:

Black Black with Blue Stripe Black with Green Stripe Green with Orange Stripe

and coming from the sensor: White White Black Gray

This is how it is currently (runs this way): Black - White Black/Blue - White Blk/Green - Gray Green/Orange - Blk

I've played with as many combinations that I can and either the engine will not crank, or I get the same check engine light code. I can go purchase another o2 sensor in case this one is fried, but wanted to try to get it wired right first.

Any help would be greatly appreciated!!

Jay

Reply to
JMH
Loading thread data ...

JMH did pass the time by typing:

It's too late for this advice. Hopefully you haven't destroyed the ECU, but wiring the O2 sensor the wrong way can damage it and the ECU. When it comes to wiring, don't guess.

Unless someone here posts the pinout, your going to have to contact the dealership and get a copy of the wiring diagram. My 93 service books don't have those colors.

My suggestion is buy the service book. It will pay for itself in the first couple of repairs.

Reply to
DougW

"DougW" wrote in news:x5NUd.14234$Ps.8938@okepread06:

I figured it would do no harm at this point since the guy I got it from had already tried all combinations :-). I'll probably purchase another one as soon as I am sure the wiring is right. I'll look into a service book too.

Thanks! Jay

Reply to
JMH

Too bad the person tried to put the wrong one in. Anyone with even half a clue should know better. If the plug doesn't fit, it's the wrong thing.

You problem now is the wrong O2 colors won't ever be matched in any book so unless you know how to read the thing and have the right tools to do so, you are out of luck.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

JMH wrote:

Reply to
Mike Romain

Reply to
L.W.( ßill ) Hughes III

L.W.(ßill) Hughes III wrote in news: snipped-for-privacy@cox.net:

ah this makes sense. He did not tell me the whole story :-) I don't mind buying a new one at all, I just want to make sure I get the wiring right before I put the new one in. I need a new plug for the wiring that goes from the wiring harness, he cut that one off :-). I think I can go by the colors on the chart you mentioned below.

Thanks!! Jay

Reply to
JMH

Reply to
mic canic

never pay to be cheap, "JMH" a écrit dans le message de news: Xns960BB6EDF77E4mapsleaghcom@216.196.97.131...

Reply to
Patrick

So do you think a long strip and crimp connector would work to let the air in still? Do you know which wire carries the air charge? Not necessarily the color, but the purpose of the wire. Is it the ground or something that would make sense?

Mike

mic canic wrote:

Reply to
Mike Romain

Reply to
L.W.( ßill ) Hughes III

L.W.(ßill) Hughes III wrote in news: snipped-for-privacy@cox.net:

I've looked into this a good bit at this point. I'm going to get a service manual, it should have the page I need like stated below.

I've looked at everything I can get my hand on, including the schematics of Bosch sensors and have seen nothing mentioned about air. Not sure what that even means myself :-)

Thanks for the info! Jay

Reply to
JMH

He's right about the air charge. Not sure of the exact usage, and couldn't find it in the service manual(note time of post), but the wires to the sensor *do* indeed carry oxygen to the sensor. At GM electronics training classes we were told *not* to splice the O2 sensor wires, just for this reason. I've heard of cases where a really bad running engine, which is dumping a lot of oil into the exhaust will wick the oil up through the harness into the PCM.

-- Old Crow '82 Shovelhead FLTC 92" 'Pearl' '95 Jeep Wrangler YJ TOMKAT, BS#133, SENS, MAMBM, DOF#51, SPUNGER#2

Reply to
Old Crow

Some have the air charge coming in around the case to wires joint and some have it coming in along the insulation for one wire.

This is the outside air charge needed to compare to the inside to make the signal if any.

I asked 'mic canic' which wire because I for one don't really think he knows which O2 sensor goes where or which is which.

One type has to be crimped to 'jury rig' it to fit and the other type can be properly soldered and heat shrinked to jury rig it.

The best is still the one that fits properly......

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

"L.W.(ßill) Hughes III" wrote:

Reply to
Mike Romain

I've heard the same story about O2 sensors and one I replaced in a Mitsubishi PU several years back came with very detailed instructions on how to coil any excess leads, don't pinch or kink the lead, why you couldn't cut the lead off, etc. Same for an old Buick - but these were the old single wire type of 15-20 years ago so I'm not sure how they apply to current sensors. They've made at least some progress in the last 15 years.

Reply to
Will Honea

the o2 sensor must have a fresh air source outside the exhaust source for comparison like mike stated and the o2's receive that from the the o2 sensor wiring. again you should never solder or crimp a o2 wire below the connector going to the o2 sensor a 02 can even detect fresh air coming down the exhaust from higher up and send bad signals( reports )to the pcm which in turn results in poor fuel management adaptives and will result in a check engine lite to make a long story short and i did not even mention 02 heater circuts hence the 4 wires and the sensors now

Mike Roma> Some have the air charge coming in around the case to wires joint and

Reply to
mic canic

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.