1/4 CEL just came on | FerrariChat
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1/4 CEL just came on

Discussion in '348/355' started by jm348ts, Jul 25, 2011.

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  1. jm348ts

    jm348ts Karting

    Oct 22, 2009
    95
    New York
    Full Name:
    John Moy
    #1 jm348ts, Jul 25, 2011
    Last edited: Jul 25, 2011
    the 1/4 CEL just came on last week but went away. This week it came on and stayed. Having read the threads on this issue I removed the cover behind the passenger seat to "pull the codes". No button. I know that I can and will order the test wire and button but I could not find where this should be connected to. There is a small capped off wire that comes off of one of the large wire bundles. Is this where the test wire is connected?

    Most of my difficulties so far seem to be electrical contact problems. My garage is a bit damp so that makes things even worse. With the CEL light on, I experience no difficulty starting, no loss of power, I don't think it idles any differently, and lastly, the cats don't seem any hotter than usual. They were certainly not red hot and the crackling sound from the hot exhaust system went away in about 15 minutes, normal I think for a 90 degree day. The passenger side was not any hotter than the drivers side either.

    If bad contacts are the problem here too, is it worthwhile cleaning the cat ecu, o2, and thermocouple (don't know what/where this is) contacts and then clear the codes afterwards to see if they reappear? Or is this not a good idea?

    Any and all advise is greatly appreciated as always.
     
  2. plugzit

    plugzit F1 Veteran
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    Dec 1, 2004
    7,779
    Redondo Beach, CA
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    Bruce Bogart
    #2 plugzit, Jul 25, 2011
    Change them side to side, one by one. When the CEL changes sides, you've identified the source of the problem. That's one of the great benefits of having a 348 over a 355. Use the cash you save by identifying and fixing the problem yourself to buy a SRI gold kit and say bye-bye to those little problems!
     
  3. jm348ts

    jm348ts Karting

    Oct 22, 2009
    95
    New York
    Full Name:
    John Moy
    #3 jm348ts, Jul 26, 2011
    thanks for the answer about swapping the parts. I reposted my questions on the tech section of FC. But since you answered if you don't mind:

    before I actually swap each component is it not worthwhile cleaning the contacts?

    Is it okay to then clear the codes to see if this solves it?

    If this fails I will then start swapping the components.

    should I then clear the codes after changing each component to pinpoint the problem?

    once I get the test wire and button, where does it attach on the ecu?
     
  4. mpodgor

    mpodgor Formula Junior

    Aug 15, 2005
    661
    San Mateo, Ca.
    Full Name:
    Michael J Podgorski
    #4 mpodgor, Jul 26, 2011
    Have you plugged in a tester to see what codes the ecu has? I assume the 348 has OBDII.
    The tester is cheap and will show all common codes. Good place to start.
    Also. I am a firm believer in cleaning contacts. I work on 737's which have tons of plugs & sockets. I use a contact cleaner (spray) called De-Ox it. It removes oxidation on the metal contact surfaces on connectors. I have applied it to every connector I can find on my 355.
    It sure can't hurt to try. Good luck & post if you find the specific problem setting off the CEL.
     
  5. jm348ts

    jm348ts Karting

    Oct 22, 2009
    95
    New York
    Full Name:
    John Moy
    #5 jm348ts, Jul 26, 2011
    Thanks for the advise Mike. Will start cleaning. Will also get an OBDII to read the codes. I was not aware that there was a receptacle for this as all discussions refer to the ecu flashes and pauses on the dash board that show when the "button" on the ECU is pressed.
     
  6. mpodgor

    mpodgor Formula Junior

    Aug 15, 2005
    661
    San Mateo, Ca.
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    Michael J Podgorski
    #6 mpodgor, Jul 26, 2011
    Last edited: Jul 26, 2011
    I am very sure your car has the recepticle. Mine is just under the stearing wheel. I'm sure if you do some research you will find your location. Or better yet, a 348 owner chimes in and describes it. The connector is universal. It's very easy to do.You don't need to be a car expert. I got my checker on Ebay. Just look for OBDII tester.If you have a CEL then you will have at least 1 code that set it off. You can do this!
     
  7. mpodgor

    mpodgor Formula Junior

    Aug 15, 2005
    661
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    Michael J Podgorski
    #7 mpodgor, Jul 26, 2011
    OBDII is short for: On Board Diagnostics. Generation 2.
     
  8. tcannon

    tcannon Formula 3

    Feb 18, 2009
    1,763
    Norman, OK
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    Todd Cannon
    #8 tcannon, Jul 26, 2011
    348's have OBDI. You have to use the button method to retrieve the codes.
     
  9. 3forty8

    3forty8 F1 Rookie
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    Apr 25, 2006
    2,713
    San Diego
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    Eric
    #9 3forty8, Jul 26, 2011
    Last edited: Jul 26, 2011
    First off, make sure your car is a Motronic 2.7 before buying anything. The 2.5 only has one throttle position sensor on one throttle body, the other TB does not, so it is easy to identify - 2.7 systems have a TPS on each TB. I don't believe the Motronic 2.5 system has the plug in the wiring loom for the test buttons.

    Please don't waste your money on an OBDII scanner - all 348s are OBDI.

    ^^ This. Just order the buttons and wiring loom from Ricambi (assuming you have the 2.7 system), pull your codes and save yourself a lot of hours and grief blindly searching for the problem:

    Table 7a (part diagram #'s 2 and 3):
    http://www.ricambiamerica.com/parts_catalogs.php?M=FE&P=&V=diag&I=3062

    Wiring connector:
    http://www.ricambiamerica.com/product_info.php?products_id=200411

    Button:
    http://www.ricambiamerica.com/product_info.php?products_id=200364

    Then go here to learn the procedure, pull your codes and identify the problem:
    http://www.my348.com/348.html#ECUcodes

    Then report back what your codes are and someone will be able to provide more insight! :)
     
  10. jm348ts

    jm348ts Karting

    Oct 22, 2009
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    New York
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    John Moy
    #10 jm348ts, Jul 27, 2011
    Thanks Eric,
    my ECU has the small wire extending from the main bunch of wires as shown in the diagram that you sent a link for. If this means I have a Motronic 2.7 ECU, I should be in business. Once I receive the parts I'll pull the codes. Thanks again.
    John
     
  11. 3forty8

    3forty8 F1 Rookie
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    Apr 25, 2006
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    Eric
    #11 3forty8, Jul 27, 2011
    Last edited by a moderator: Sep 7, 2017
  12. jm348ts

    jm348ts Karting

    Oct 22, 2009
    95
    New York
    Full Name:
    John Moy
    #12 jm348ts, Jul 29, 2011
    Eric,
    Thanks for all the help and pics. I do have the Motronic 2.7 Will order the parts and follow through. Have a good weekend
     
  13. jm348ts

    jm348ts Karting

    Oct 22, 2009
    95
    New York
    Full Name:
    John Moy
    #13 jm348ts, Aug 3, 2011
    Eric,
    I contacted Ricambi and was told that the test wire and button was discontinued by Ferrari and unavailable. The rep said that it was easy enough to replicate using wire and a button. The electrical connection was fairly standard also. Any knowledge of anyone doing this? Thanks for your help.
     
  14. 3forty8

    3forty8 F1 Rookie
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    Apr 25, 2006
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    #14 3forty8, Aug 3, 2011
    I think you have another thread going in the tech section which I replied to, but if it were me I'd try to find a used set from a breaker rather than making one. Probably easy enough to make, but finding the correct size/shape/depth button and connector would be the hard parts (assuming you want to mount them permanently in the car like a stock set).
     
  15. tcannon

    tcannon Formula 3

    Feb 18, 2009
    1,763
    Norman, OK
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    Todd Cannon
    #15 tcannon, Aug 3, 2011
    Hello John, you may want to contact this guy to see if he has two of them available. He was parting out a '94 348 spider. I bought several items from him and they were priced well and were exactly as described. Here is a link to his ebay page. Good luck!


    http://myworld.ebay.com/slava81
     
  16. 348driver

    348driver Rookie

    Oct 15, 2009
    1
    #16 348driver, Aug 7, 2011
    This just happened to my '94 348. I would drive it about 5miles get the 1/4 CEL followed immediately by the 1/4 block shut-off limp-home mode. I pulled the ECU code and it read 4122: the "Cat Too Hot" code. I thought that my passenger side cat had gone bad.

    As a last ditch effort, I drained the gas and replaced the tank-full with fresh premium. I re-set the ECU by shutting the power off for 15 minutes. The car has operated normally ever since. It is my guess that with 10% ethanol in today's gas, that some gas has more than 10% which caused my 348 to run hot exhaust, triggering the cat's sensor. I think fuel additives will also effect the cats with hotter exhaust.

    It's easy and doesn't cost much to replace the fuel and it might be the cause of your trouble.
     
  17. Miltonian

    Miltonian F1 Veteran

    Dec 11, 2002
    5,966
    Milton, Wash.
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    Jeff B.
    #17 Miltonian, Aug 7, 2011
    Last edited: Aug 7, 2011
    If you got a 4122 code on one bank, I would guess that you have a bad exhaust temperature ECU on that bank. Pretty common. It's easy to switch the sides from left to right on the temp ECU's and see if the warning light also switches sides. (as noted above by Plugzit).

    Does your car have a stock exhaust system?
     
  18. jm348ts

    jm348ts Karting

    Oct 22, 2009
    95
    New York
    Full Name:
    John Moy
    #18 jm348ts, Aug 7, 2011
    Thanks Eric, will keep searching. Russ at Ferrparts is trying to locate one.

    Thanks Todd, I emailed the guy on ebay. Hope he has one.

    348Driver, I don't get the 1/4 limp home light and the cats don't seem very hot at all. In fact all seems fairly normal.

    Jeff and all brotherhood, at one point if I don't turn up the test wire and button and nobody comes up with instructions to replicate the wire what items would you start trying first. Ground wire on the O2 Sensor? Start swapping cat ecu's?

    All help is badly needed.

    And thanks!
     

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