O2 Sensor Connector Location? - Alfa Romeo Bulletin Board & Forums
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 19 (permalink) Old 03-23-2004, 10:13 AM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
Question O2 Sensor Connector Location?

Can anyone give me a quick tip on where the oxygen sensor connector is located in the engine bay on an S4 Spider? I'm trying to troubleshoot a pesky check engine light.

Also, the Cardisc CD doesn't seem to have the Bosch wiring diagrams? They're listed in the table of contents for the chapter on the electrical system, but the pages aren't there. Anyone else notice this? If I could find them I'd at least know what color wires I'm looking for...
Gubi is online now  
Sponsored Links
Advertisement
 
post #2 of 19 (permalink) Old 03-23-2004, 10:25 AM
Registered User
Platinum Subscriber
 
John M's Avatar
 
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 4,404
Send a message via AIM to John M Send a message via Yahoo to John M
Hey Gubi:

Its runs down the fire wall above the exhaust manifold and next to the booster/pedal box.

Best Regards,
John M

[SIZE="1"]1978 AR Spider Veloce 2000....the first and still here...Bianco
1984 AR Spider Veloce............the second & gone to the parts bin....Rosso
1992 AR Spider Veloce............the third and still here...Bianco
1991 AR 164L........................the fourth and traded on the SS....Rosso
1965 AR Sprint Speciale..........the fifth...in boxes....sold....Bianco
1978 AR Spider Veloce 2000....the sixth gone to be a parts car...slow black
1993 AR Spider Veloce...........the seventh, freshening up to be sold....Verde Inglese
1982 Ferrari 308 GTSi.............the first, fresh restore....Azzurro[/SIZE]
John M is offline  
post #3 of 19 (permalink) Old 03-23-2004, 11:26 AM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
Thanks John. There was one three-wire connector there when I looked last night...I'm assuming that's it?

You don't have a wiring diagram by any chance, or know where it is on the Cardisc?
Gubi is online now  
post #4 of 19 (permalink) Old 03-23-2004, 12:58 PM
Registered User
Platinum Subscriber
 
John M's Avatar
 
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 4,404
Send a message via AIM to John M Send a message via Yahoo to John M
Hey Gubi:

I think its a two wire. One heater, one reading. Right in that same vicinity there are a couple more wires. Don't know what they are for, but best guess is reverse lights. I will snap a picture of the two you are looking for and post up in a little while.

Best Regards,
John M

[SIZE="1"]1978 AR Spider Veloce 2000....the first and still here...Bianco
1984 AR Spider Veloce............the second & gone to the parts bin....Rosso
1992 AR Spider Veloce............the third and still here...Bianco
1991 AR 164L........................the fourth and traded on the SS....Rosso
1965 AR Sprint Speciale..........the fifth...in boxes....sold....Bianco
1978 AR Spider Veloce 2000....the sixth gone to be a parts car...slow black
1993 AR Spider Veloce...........the seventh, freshening up to be sold....Verde Inglese
1982 Ferrari 308 GTSi.............the first, fresh restore....Azzurro[/SIZE]
John M is offline  
post #5 of 19 (permalink) Old 03-23-2004, 01:24 PM
Registered User
 
turbolarespider's Avatar
 
Join Date: Apr 2003
Posts: 1,835
John
If its a heated sensor, it's either 3 or 4 wires. Being that the car is an early 90's, it would be 3 wire heated.

Gubi
They can be a real PITA to remove, so be careful. Threads can be easily damaged when removing, let alone putting back in.

Eric
turbolarespider is offline  
post #6 of 19 (permalink) Old 03-23-2004, 01:59 PM
Registered User
Platinum Subscriber
 
John M's Avatar
 
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 4,404
Send a message via AIM to John M Send a message via Yahoo to John M
Hey Gubi and Eric:

Eric, you are right, its a three wire. Gubi, it has two connectors under the hood. The box connector has two white wires coming out and I believe that is the heater. The round orange cap connector is the computer feed. You can take your measurements from that connector with the red lead on a digital multimeter.

You can see these two connectors on cardisc under Service Manual - Fuel System on page 21.

Here is a picture of the two connectors you are looking for. Be sure to keep these wires off the manifold if you have to reinstall a new one.

Best Regards,
John M
Attached Images
 

[SIZE="1"]1978 AR Spider Veloce 2000....the first and still here...Bianco
1984 AR Spider Veloce............the second & gone to the parts bin....Rosso
1992 AR Spider Veloce............the third and still here...Bianco
1991 AR 164L........................the fourth and traded on the SS....Rosso
1965 AR Sprint Speciale..........the fifth...in boxes....sold....Bianco
1978 AR Spider Veloce 2000....the sixth gone to be a parts car...slow black
1993 AR Spider Veloce...........the seventh, freshening up to be sold....Verde Inglese
1982 Ferrari 308 GTSi.............the first, fresh restore....Azzurro[/SIZE]
John M is offline  
post #7 of 19 (permalink) Old 03-23-2004, 02:52 PM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
Thanks guys, you rock.

In case you're wondering, John, I'm checking this because my "Intermittent 1223 Code" problem has started to become an "Irritatingly Frequent 1223 Code with Occasional 1224" problem.
Gubi is online now  
post #8 of 19 (permalink) Old 03-24-2004, 02:06 AM
Registered User
Platinum Subscriber
 
John M's Avatar
 
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 4,404
Send a message via AIM to John M Send a message via Yahoo to John M
Hey Gubi:

Good deal. Let me know what yours is doing. Mine has all but quit it....but I bet it will return. I ran the hell out of it over the weekend. So maybe it decided to fly right so to speak.

Best Regards,
John M

[SIZE="1"]1978 AR Spider Veloce 2000....the first and still here...Bianco
1984 AR Spider Veloce............the second & gone to the parts bin....Rosso
1992 AR Spider Veloce............the third and still here...Bianco
1991 AR 164L........................the fourth and traded on the SS....Rosso
1965 AR Sprint Speciale..........the fifth...in boxes....sold....Bianco
1978 AR Spider Veloce 2000....the sixth gone to be a parts car...slow black
1993 AR Spider Veloce...........the seventh, freshening up to be sold....Verde Inglese
1982 Ferrari 308 GTSi.............the first, fresh restore....Azzurro[/SIZE]
John M is offline  
post #9 of 19 (permalink) Old 03-24-2004, 11:41 AM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
Hmmm...well I tested it last night and it's bouncing between 0.2 and 0.8 volts, which from reading the service manual is pretty much what it's supposed to be doing. However, I couldn't get the light to come on while I was testing it, so it's possible I have an intermittent bad connection somewhere. It's also possible it's clogged injectors, a failing air mass flowmeter, or an air leak somewhere that I can't find.

I'm taking it in to my mechanic on Saturday so we can slap it on the emissions meter and figure out exactly what's going on...at this point I'm not sure if it's lean or rich. Hopefully some additional testing will shed light on the issue.
Gubi is online now  
post #10 of 19 (permalink) Old 03-24-2004, 12:35 PM
Registered User
Platinum Subscriber
 
John M's Avatar
 
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 4,404
Send a message via AIM to John M Send a message via Yahoo to John M
Hey Gubi:

Did it ever settle down on a number? Like was it mostly in the .4s? Takes awhile it seems.

Best Regards,
John M

[SIZE="1"]1978 AR Spider Veloce 2000....the first and still here...Bianco
1984 AR Spider Veloce............the second & gone to the parts bin....Rosso
1992 AR Spider Veloce............the third and still here...Bianco
1991 AR 164L........................the fourth and traded on the SS....Rosso
1965 AR Sprint Speciale..........the fifth...in boxes....sold....Bianco
1978 AR Spider Veloce 2000....the sixth gone to be a parts car...slow black
1993 AR Spider Veloce...........the seventh, freshening up to be sold....Verde Inglese
1982 Ferrari 308 GTSi.............the first, fresh restore....Azzurro[/SIZE]
John M is offline  
post #11 of 19 (permalink) Old 03-24-2004, 01:08 PM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
No, it didn't stabilize. When I first started it (engine was semi-warm) it was hovering around a stable 0.47, but then as it warmed up it started moving up and down between about 0.2 and 0.8. Only ran it about 10min, though. The service manual said something like "should move between 0 and 1 volts" or something like that, so I'm assuming this is normal behavior. Should it be doing something else?
Gubi is online now  
post #12 of 19 (permalink) Old 03-24-2004, 04:53 PM
Registered User
Platinum Subscriber
 
John M's Avatar
 
Join Date: Mar 2003
Location: Mount Sterling, KY
Posts: 4,404
Send a message via AIM to John M Send a message via Yahoo to John M
Hey Gubi:

That sounds good that it started off where it belongs. Sounds like you got something other than the O2 sensor. I would check all those hoses very carefully. Across the top of the motor and the intake rubber runners as well.

Best Regards,
John M

[SIZE="1"]1978 AR Spider Veloce 2000....the first and still here...Bianco
1984 AR Spider Veloce............the second & gone to the parts bin....Rosso
1992 AR Spider Veloce............the third and still here...Bianco
1991 AR 164L........................the fourth and traded on the SS....Rosso
1965 AR Sprint Speciale..........the fifth...in boxes....sold....Bianco
1978 AR Spider Veloce 2000....the sixth gone to be a parts car...slow black
1993 AR Spider Veloce...........the seventh, freshening up to be sold....Verde Inglese
1982 Ferrari 308 GTSi.............the first, fresh restore....Azzurro[/SIZE]
John M is offline  
post #13 of 19 (permalink) Old 03-24-2004, 10:35 PM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
I dunno, man, those hoses look pretty good. I even pulled off the hose to the carbon cannister just to see what it would do with a big intentional leak - didn't make a lick of difference.

My money right now is on an intermittent bad connection to the O2 sensor. Failing that, I'm going to look at the AFM calibration and double-check the fuel pressure. Could also just be clogged injectors, I suppose, but the engine power seems fine.
Gubi is online now  
post #14 of 19 (permalink) Old 03-25-2004, 04:44 AM
Registered User
 
turbolarespider's Avatar
 
Join Date: Apr 2003
Posts: 1,835
Gubi
What code are you getting?- or what do the codes you posted mean?

Switching between .2 and .8 is not only normal, it also indicates that it's not very worn either...

Eric
turbolarespider is offline  
post #15 of 19 (permalink) Old 03-25-2004, 09:38 AM Thread Starter
But Mad North-Northwest
Platinum Subscriber
 
Gubi's Avatar
 
Join Date: Sep 2003
Location: SF Bay Area, CA
Posts: 7,389
Yeah, the sensor's pretty new - I just had it installed in October. Old one had 85k on it, so I figured it was definitely time.

I don't have my Cardisc here, but if I recall correctly the 1223 code means "lambda sensor at control limit" or something like that. The 1224, which I only saw once, is that the lambda sensor voltage is out of range.
Gubi is online now  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Alfa Romeo Bulletin Board & Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome