02 sensor help | FerrariChat
Buy

02 sensor help

Discussion in 'Technical Q&A' started by tasty348, Mar 29, 2006.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. tasty348

    tasty348 Karting

    Jan 13, 2006
    210
    Ocean City, Maryland
    Full Name:
    Christopher and Amy
    #1 tasty348, Mar 29, 2006
    I am trying to break loose the o2 sensors, but no luck. I have sprayed some penetrating lub to assist. There is very little room so only a little leverage is available. It feels like I'll have enough to break it loose though, it just isn't budging. Is it easier to take the wheel off to get to them? Any thoughts??? I tried my adjustable 22mm hinging socket wrench however the rounded edge of the wrench slighly overlaps the open-ended socket and the sensor itself is in the way.('91 348)
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    BANNED Lifetime Rossa

    Jan 11, 2001
    26,822
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #2 Steve Magnusson, Mar 29, 2006
    They make special 6-point deep socket with a slot cut into the side just for this problem (the high temp cycling/cooking making it a b*tch to get apart -- even with this special socket) -- almost any autoparts or hardware store can provide, or easily ordered on-line (and it won't be f-priced ;)). Here's just one example:

    http://www.toolsource.com/ost/product.asp?sourceid=overture&dept%5Fid=500&pf%5Fid=67696&mscssid=T1PC1V89DUE68MDP4HWWPWV35JAHDJQB

    (but I've seen them for as little as $5~6) -- just search on something like "O2 sensor socket".
     
  3. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    #3 Mark 328, Mar 29, 2006
    Not familiar with the 348, but sometimes the sensors are easier to get off with an open end wrench (maybe 7/8 inch for the 348?).
    Also, you can make a socket with a Harbor Freight (or another inexpensive) impact socket and then cut the slot with a cutoff wheel.

    Mark
     
  4. tasty348

    tasty348 Karting

    Jan 13, 2006
    210
    Ocean City, Maryland
    Full Name:
    Christopher and Amy
    #4 tasty348, Mar 29, 2006
    Thanks for the help. As always, exactly what I needed. The socket is ordered and on the way.
     
  5. tasty348

    tasty348 Karting

    Jan 13, 2006
    210
    Ocean City, Maryland
    Full Name:
    Christopher and Amy
    #5 tasty348, Mar 29, 2006
    I purchased the Bosch # 15727 and it comes with a sqaure plastic sleeve. I am wondering once I splice the wires together and rebuild with this plastic sleeve, is it best to cut and reassemble closer to the sensor or closer to where the sensor goes in to the engine?
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    BANNED Lifetime Rossa

    Jan 11, 2001
    26,822
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #6 Steve Magnusson, Mar 29, 2006
    I can't really give an opinion on where you should place the splice because I'm not familiar enough with your model. As long as you keep in mind that things are hot (so the routing and placement should try to minimize any thermal exposure to the wire or splice) it will work OK, but I'd put a high priority on asthetics too (e.g., hiding the splice as best as possible).
     
  7. Ferrari Fanatic

    Ferrari Fanatic Formula 3

    Apr 2, 2003
    1,317
    SoCal
    #7 Ferrari Fanatic, Mar 29, 2006
    The last person who installed that O2 sensor should have put some anti-sieze compound on the threads, that would have definetly helped.

    Be careful to not torque on your cat too much when it is still attached to the headers. On the 355 (I know you have a 348) cracking is a huge problem so you don't even want to go there.
     
  8. T-A Tech

    T-A Tech Rookie

    Sep 16, 2005
    49
    Western Massachusett
    Full Name:
    Jim Burke
    #8 T-A Tech, Mar 29, 2006
    Just replaced both O2 sensors this past Monday ('92 TS). Soaked 'em good overnight with PB Blaster, took off the rear wheels and got at the sensors through the rear suspension control arms. Used the special socket ($8.00 at AutoZone). It was a tight fit sliding it down over the old sensors - took a little persuasion-but they broke loose easier than I expected.

    Replaced with the 15727 universals from Bosch. Anti-seize is already on them from the factory. I left more wire than the instructions suggested on the plug end when I cut them off, and was happy I did. I fitted the Bosch connection box as close to the plug connectors as I could. It now sits tie-wrapped under the air filter box - you can't see it from above - plus it's out if the direct heat from the cats.

    While I had everything apart, I also took an extra 10 minutes to install extra 14GA ground wires from the sensor body to a good chassis ground.

    Hope this cures my CEL Lamda codes!

    YMMV - Jimbo
     

Share This Page