360 - Ferrari 360 CEL and slow down light | FerrariChat

360 Ferrari 360 CEL and slow down light

Discussion in '360/430' started by peterdavid911, Mar 27, 2020.

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  1. peterdavid911

    peterdavid911 Formula 3

    Apr 9, 2012
    1,339
    London, UK
    Full Name:
    Peter
    Hi everyone, I have a 2005 360 F1 with 12,600 miles, UK car. All original with CATS, no modifications at all.

    Recently I had the CEL light come on after moderate easy driving of about 3 miles and the car seemed to sun a bit rough. I did the ECU rest by switching the power off overnight and all was well. I changed both MAFS after this event.
    Yesterday the car was idling rough from the start again and also while driving had loss of power too. I noticed the Slow Down light flash on very briefly. The CEL came on a few minutes after and stayed on. This all started after about 3 miles of driving again in low revs. I noticed that the slow down light would flash every time I changed gear, up or down it did the same. It was such a quick flash only at gear changes that it was hardly noticeable but it was there.

    Any ideas on what the could be? I don't have an OBD2 reader but recommendations on which to buy would be great.

    Many thanks.
    Peter
     
  2. Bob in Texas

    Bob in Texas F1 Rookie

    Apr 23, 2012
    2,665
    Just East of Weird
    Full Name:
    Bob
    One possibility is an aging 360 ECU - aging ECU’s can cause a slow down light. There are 2 ECU’s, one for each side.
    Bad grounds on the ECU’s have also been mentioned as a cause for slow down lights. Cleaning the grounds have cured the problem for some folks. Others needed new ECU’s.
    (Environmental control unit)


    Sent from my iPad using Tapatalk Pro
     
  3. wbt

    wbt Karting

    Nov 28, 2014
    231
    New Zealand
    Full Name:
    Wayne
    There's a few causes of the fault in order of most likely to least likely: Cat ECU fault, thermocouple lead broken, genuine misfire (coils, air / fuel problem, spark related). You will need to read the OBD II code to be 100% sure what the fault is - a cheap ebay code reader and a free app can help here (motordata can read both engine ECU's). Generally an easy to solve problem.
    https://technistrada.com/content/7-ferrari-slow-down-light-explained

    ECU reset by power cycling is not recommended - faults don't often go away by themselves and it's much more useful to read the code than lose it.
     
  4. artsd

    artsd Formula Junior
    Owner

    May 6, 2009
    280
    Full Name:
    Art
    I got the Gemwon ELM327 wi-if based OBD reader from Amazon for $15. I heard that wi-fi was more reliable than Bluetooth on OBD readers but don’t have experience to say for sure.

    I am using the $10 iOS OCTech OBD Fusion app.

    This combination works with the dual ECUs in the 360. Once connected, the app prompts for which ECU you want to use. Mine are always shown as ECU 11 and ECU 14 for some reason. To switch ECUs I have to disconnect from the wi-fi access point provided by the Gemwon and reconnect which is a small pain.
     
    Grande Fiume likes this.
  5. RedNeck

    RedNeck F1 Veteran
    Silver Subscribed

    Jul 8, 2016
    9,803
    The CSA
    Full Name:
    Me
    First off, stop throwing parts at your car without knowing what code it is throwing. Get a code reader or don't attempt to work on your own car. It will only end up with you wasting money and chasing your tail.

    The most likely culprit is your cat ECU's, they have been known to fail as mine did. I replaced both of mine with aftermarket units that do not have the issues the Ferrari ones do, not to mention are cheaper. I highly doubt after 3 miles of driving that you are getting legitimate temp codes.

    Get a code reader and that will tell you what side the issue is coming from, inspect the thermocouple and then replace the ECU if that looks ok. It's a 5 minute job once you have the side cover off, which is also a 5 minute job.
     
    one4torque and SonnyCrocket like this.
  6. spider348

    spider348 Formula 3

    Nov 3, 2003
    1,264
    MA
    Full Name:
    John
    Had a similar issue with my 360. Checked cat temp with my IR gun to confirm no overheating. Removed Cat Temp ECU connectors and carefully cleaned all connections. Problem solved.
    Had same issue with my prior F355 as well. Old cars. Connections fail.
    Code reader needed with these old Ferraris as others have recommended.
     
  7. peterdavid911

    peterdavid911 Formula 3

    Apr 9, 2012
    1,339
    London, UK
    Full Name:
    Peter
    Thanks guys, looks like there a a few known culprits such as the cat ECUs, thermocouple sensors, sparks and coils. I will buy a OBD2 sensor and see what codes I get, can anyone recommend a good one for these cars?
    I might change the above items as it seems to be good preventative maintenance as these cars are getting older now and still have the original parts. My cat ECUs are the green base ones. The car is from 2005 and are probably the original ones still.
    Does anyone know if the thermocouple is connected to the cats underneath the car which means the under trays need removing?
    Many thanks.
     
    Grande Fiume likes this.
  8. RedNeck

    RedNeck F1 Veteran
    Silver Subscribed

    Jul 8, 2016
    9,803
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    No, you can get to all of it through the top.
     
    Grande Fiume likes this.
  9. Grande Fiume

    Grande Fiume Rookie

    Mar 30, 2020
    2
    Creede, CO
    Full Name:
    Courtney La Zier
    Great info to file away. Thanks folks!
     
  10. BrettC

    BrettC Formula 3

    Aug 13, 2012
    1,966
    Calif
    Full Name:
    Brett
    I had to replace both exhaust ecu's and thermocouplers...fixed
     
  11. peterdavid911

    peterdavid911 Formula 3

    Apr 9, 2012
    1,339
    London, UK
    Full Name:
    Peter
    Did you use the original Ferrari cat ecu's? There is an aftermarket one by Technistrada but not sure if anyone has used them.
     
  12. SonnyCrocket

    SonnyCrocket Rookie
    Silver Subscribed

    May 26, 2018
    18
    Used Technistrada and have no regrets.
     
  13. artsd

    artsd Formula Junior
    Owner

    May 6, 2009
    280
    Full Name:
    Art
    Same. Bought 2 even though only 1 side was failing. Cheap enough to have handy for when the other side goes out which is inevitable with heat cycles and moisture.
     
  14. peterdavid911

    peterdavid911 Formula 3

    Apr 9, 2012
    1,339
    London, UK
    Full Name:
    Peter
    I have been looking at the CAT ECUs, part number 179278 and found that Maserati use the exact same part number and the images of it also has the Ferrari logo stamped on the side of it.
    The price is considerably lower. Has anyone used the Maserati part and any issues?
    Many thanks.
     
  15. I'm 360 Canuck

    I'm 360 Canuck Formula 3

    Nov 21, 2015
    1,911
    Ontario, The Real One in Canada
    Full Name:
    Lars!
    When I had that issue it stemmed from a weaker battery....even though the battery had no issues starting the car.
    If you battery is 2-3+ years old, I would start there.
    it was frustrating to have such a dramatic issue stem from such a minor issue, but it is what it is.
     
    one4torque likes this.
  16. peterdavid911

    peterdavid911 Formula 3

    Apr 9, 2012
    1,339
    London, UK
    Full Name:
    Peter
    Thanks that's very interesting. I've heard the issues that weak batteries can have.
    My battery is always on the C Tek charger and I never take it off. It was on all 8 led lights when I took the car out. With that in mind the battery should be ok I assume.
     
  17. I'm 360 Canuck

    I'm 360 Canuck Formula 3

    Nov 21, 2015
    1,911
    Ontario, The Real One in Canada
    Full Name:
    Lars!
    mine was always on a charger too :) As they age, their potential to take and hold a charge deteriorates it seems, much like the battery in a cell phone.

    I used to scoff at those on this site that advocated changing their batteries for no cause every 3 years, because ive ran batteries for 9 years on my daily driver Audi and Dodge... but after this situation, im not so sure.
    at any rate, I bought the most expensive agm battery I could find :)
    just for fun, throw a load tester onto your battery and see. way cheaper than cat ECU's :)

    I still use the old battery around the garage and yard to run 12v items...just not my fussy Ferrari.
     
    Apollo 11 likes this.
  18. peterdavid911

    peterdavid911 Formula 3

    Apr 9, 2012
    1,339
    London, UK
    Full Name:
    Peter
    Problem solved!
    I took my car to a specialist as the problem seemed worse with misfire and rough running. Plugged it into an SD2 and ended being a dead spark plug on cylinder 1 and a bad 02 sensor. I ended up changing all the plugs, all coils, 02 sensors and it fixed the problems.
    Had a long 80 mile drive home and ran great:)
     
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