95 355 Running on half its cylinders?? | FerrariChat

95 355 Running on half its cylinders??

Discussion in 'Technical Q&A' started by Rjones355, Jul 30, 2004.

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  1. Rjones355

    Rjones355 Karting

    Jul 6, 2004
    62
    Rancho Murieta, CA
    Full Name:
    Ryan Jones
    It appears that my car is running on half its cylinders. When this first happened I was told to disconnect the catalytic sensors on the quarter panels, because when they fail they shut off half the fuel system. So I unplugged those and my power came back. I have since then changed those 2 sensors, and everything has been running fine.
    But this morning it was making a little more noise than usual when I started the car. Usually it makes a little rattling noise when I start the car in the morning than in about a minute or 2 it warms up and sounds great. This time it was a little longer than usual. Then when I started driving it, I could immediatly tell that it was not running right. So I pulled over and unplugged the sensors, thinking that they were bad. This time it didn't help. Still the same, missing and it seemed as if it was running on half cylinders.
    Any help, or any idea to point me in. Assides from the dealer.
     
  2. goyal99

    goyal99 Karting

    Mar 5, 2002
    185
    Upstate NY - USA
    Full Name:
    V K
    Do you get any lights coming on when this happens, like the "check Engine" light or the "slow down" light(s)??

    Do you have cats in your car???

    Post more details - VK
     
  3. Rjones355

    Rjones355 Karting

    Jul 6, 2004
    62
    Rancho Murieta, CA
    Full Name:
    Ryan Jones
    No lights. Last time that I had the cat sensor problem, the slow down light was coming on. This time there are no lights coming on. just a loss in power. Im having some a/c problems, which Im sure are unrelated, I have the compressor unplugged, I have to put a new one on. The cats are hallowed out and they are running like staright pipes. I just found this out after asking the original owner.
     
  4. Rjones355

    Rjones355 Karting

    Jul 6, 2004
    62
    Rancho Murieta, CA
    Full Name:
    Ryan Jones
    Someone told me to try the fuses for the fuel pump. Make sure they are good, and if they are unplug each one while the car is running, at least to find out what side of fuel is bad. Does that make sense, does anyone know if those fuses are in the RH side floor area?
     
  5. GTO84

    GTO84 Formula Junior

    Dec 13, 2003
    565
    Passengers foot rest plate. Two screws at the top. Fuel pump fuse is in there. Don't know if that will help though. I would check the ignition modules, as they can fail too.
     
  6. Rjones355

    Rjones355 Karting

    Jul 6, 2004
    62
    Rancho Murieta, CA
    Full Name:
    Ryan Jones
    Do you happen to know where the ignition modules are located? I can check those also.

    Thanks
     
  7. goyal99

    goyal99 Karting

    Mar 5, 2002
    185
    Upstate NY - USA
    Full Name:
    V K
    I seriously doubt your problem is with the fuel pump(s)....There should be two (2) and 2 fuel filters in your car....I would look to change the filters first before messing with the fuel pumps.

    It could be a problem with your fuel injection/MAF sensors....I have a similar problem with my car related to the Mass Flow Sensors....but has nothing to do with fuel pumps/injectors.

    Do you know how to read the error codes from the car's ECU computers?? I would look there first to see if you get any error codes...Do a search in the archives for the procedure to extract the ECU error codes.

    I'm still wondering why you're not getting ANY lights on your dash panel....If the car is running on only one bank (as you stated above) the CHECK ENGINE light should be glowing brightly while the car is running....Does it at least come on when your first start the car and does it go out after a few seconds?? (check status)..

    VK
     
  8. GTO84

    GTO84 Formula Junior

    Dec 13, 2003
    565
    Here
     
  9. Rjones355

    Rjones355 Karting

    Jul 6, 2004
    62
    Rancho Murieta, CA
    Full Name:
    Ryan Jones
    Thanks for the picture, is there a way to test them to see if they are failling?
     
  10. GTO84

    GTO84 Formula Junior

    Dec 13, 2003
    565
    First thing you do is get in the car, look at the warning lights, and turn the key on. Does the check engine light come on?
     
  11. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    25,112
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    Determine which bank is not firing and then swap the modules to see if the problem follows to the other bank or not.

    Have you checked your OM for ignition system information -- might be helpful...
     
  12. tbakowsky

    tbakowsky F1 World Champ
    Consultant Professional Ferrari Technician

    Sep 18, 2002
    19,378
    The Cold North
    Full Name:
    Tom
    One other very easy and quick thing to check.

    Have you had the car recently engine out serviced? If so remove the panel behined the passenger seat(2 philips screws and slide panel up) Have a look at the E.c.U harness were it disappears through the firewall. Around the harness should be a rubber grommet, to protect the wiring from rubbing and getting cut/shorted on the sharp metal of the firewall. I have seen many 355's with all kinds of silly problems caused by the service tech not putting this grommet back in place.

    Just somthing quick and easy to check.
     
  13. Rjones355

    Rjones355 Karting

    Jul 6, 2004
    62
    Rancho Murieta, CA
    Full Name:
    Ryan Jones
    I cant beleive this car. I unpluged the ignition modules, unplugged the fuel pump fuses. The car now is running fine. I dont know if my Ferrari is typical, but it seems to always have these intermitant problems. Something is still obviously wrong with the car, but right now it is running fine. This is my first Ferrari, but is this somewhat normal. One day it is running great, the next day im running on 4 cylinders????
     
  14. Joe G.

    Joe G. Formula 3
    BANNED

    Dec 9, 2003
    1,109
    Los Angeles
    Full Name:
    Joe Gazzani
    Tom

    i thought 1995's had the ecu's in the back ?

    -not through the firewall deal-
     
  15. tbakowsky

    tbakowsky F1 World Champ
    Consultant Professional Ferrari Technician

    Sep 18, 2002
    19,378
    The Cold North
    Full Name:
    Tom
    #15 tbakowsky, Jul 31, 2004
    Last edited by a moderator: Sep 7, 2017
    D'oh!! Your 100% correct..I didn't realize that his car was a 95 because I did not read the title carefuly enough. My mistake!! I guess I owe myself one of these:
    Image Unavailable, Please Login
     
  16. markcF355

    markcF355 F1 Rookie
    Rossa Subscribed

    Jun 6, 2004
    3,493
    Schmeckelstan
    Full Name:
    Mark
    If there are no ECU codes it might be an intermittent ignition coil on one of the cylinder banks. Try to take notice of the exhaust smell when it’s running rough. If it smells really funky of raw fuel of if your cats are not hollow it might have that cat stink. I can’t think of a easy way the verify this other than checking the spark plugs for fouling after its been running crappy for a little while.
     

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