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360 DIY 360 Modena manual swap + "while I'm in there"

Discussion in '360/430' started by aventari, Mar 6, 2025.

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  1. GogglesPisano

    GogglesPisano F1 Rookie
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    #51 GogglesPisano, May 1, 2025
    Or a boat repair place. Tons of those. I've used them in the past for general fiberglass work. There's always some guy that does side work for cheap. Usually posts on craigslist.
     
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  2. aventari

    aventari Karting

    Dec 9, 2010
    190
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    #52 aventari, May 1, 2025
    Oh great suggestions, thanks guys!

    Living in San Diego that should be zero problem ;)
     
  3. aventari

    aventari Karting

    Dec 9, 2010
    190
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    #53 aventari, May 14, 2025
    I got the AC compressor back, looks decent.. Added 3oz of PAG 150 oil and installed it

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    First the AC line shielding was looking pretty bad so I put some DEI velcro shielding on it.

    I also replaced the orings in the lines where they connect to the hard lines.
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    Finished the extra heat shielding and install it on the compressor

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    Are you seeing a theme with heat shielding? lol :cool:

    I replaced the idler pulley and the tensioner pulley too. They looked rough and had a lot of drag. They weren't loose or anything, but I did it preventatively.

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    After installing the compressor, new pulleys and the belt and tightening it, time to fill up.

    First you pull a vacuum on the system for at least 30 minutes, I did about 2 hours to be safe, then you fill up with R134. I filled with 750g aka 1.653lbs

    You should replace the drier too, but I did that last year when I was trying to fix the AC in the first place and failing.

    So the compressor was acting kinda funny, it was hard to make it cycle on, even jumping it at the compressor relay socket. I eventually got it working and pulling R134. But it would stop running and I'd have to shut the car down. The compressor relay was also getting super hot. I switched it with the reverse relay and it didn't matter.

    I found out my left fan isn't working, maybe that's the problem? I'm going to troubleshoot that next... Anyway I've had it for about a week with AC kind of working and its nice. Hopefully I can get it sorted out and the R134 doesn't all leak out somewhere else.

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  4. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #54 aventari, May 14, 2025
    I decided to troubleshoot the RH radiator fan today (I mistakenly said left above)
    @Qavion helped me out a LOT with an electrical wiring diagram to follow to troubleshoot.

    After checking out wiring and relays and everything I figured out the resistor pack was broken. It's an open circuit.

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    Inside you can see what I thought was a diode, and after some probing with an voltmeter, I figured out the resistor coil was fine, but the "diode" was broken, and it's wired in series with the resistor so the whole thing failed.

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    I took it out and checked the numbers and it's actually a thermal fuse. I already ordered a pack of 10 and i'll fix it tomorrow.

    The numbers are: MICROTEMP EJCAFG G4A00 184c

    EJAFG must be the lot
    G4A00 is the part number
    184c obviously the temp it blows at

    I think the resistor value was like 0.7 ohms.

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    That was the low-speed part of the fan, I needed to see why the high-speed wasn't working.

    More troubleshooting, I figured out the fan would work if I jumpered the fan switch wiring, so that pretty much narrows it down to the switch itself, because the low-speed part of the switch works.

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    This 2 speed switch is $130 shipped! https://awitalian.com/product/temperature-sender-176322.html/

    Ridiculous when a VW sender that does the same thing is $9 https://www.autohausaz.com/pn/JP-251959481K

    I might design a wiring adapter so you could just plug in your stock plug in without cutting the harness... Would anyone be interested? Plus you could get the fans coming on at a lower temp if you wanted.
     
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  5. Qavion

    Qavion F1 World Champ
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    #55 Qavion, May 14, 2025
    Last edited: May 14, 2025
    Interesting. I see this brochure explains the operation of the (non-resettable) fuse.


    https://www.melchioni-ready.com/media/assets/files/g4a00/reference/g4a00.pdf?srsltid=AfmBOopYHW4Um_lwuEghR2y_5FiAhBkUL608XVilMI_hwN4pcAGZ5twc

    You did well with your diagnosis considering there were two faults.

    I'll try and update my diagrams to show the fuse. I'll put it on the green wire unless you state otherwise.
     
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  6. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #56 aventari, May 14, 2025
    Yeah sounds good. And thanks, it's a fairly simple circuit as long as there is a wiring diagram to trace the faults through. I'm still amazed Ferrari doesn't have proper ones in their manuals, but that's where you come in--it would've been very difficult without the diagrams--so thank you again!
     
  7. Qavion

    Qavion F1 World Champ
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    #57 Qavion, May 15, 2025
    I wonder if Ferrari dealers have access to proper diagrams. It must be tough diagnosing defects without them.
     
  8. aventari

    aventari Karting

    Dec 9, 2010
    190
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    #58 aventari, May 15, 2025
    Yeah ^^ I'll ask my buddy at the local shop (GP Autoworks) who was a Ferrari master mechanic for like 20 years.

    So I think I found a budget alternative to the $120 OEM fan switch.

    It's for a Fiat Punto. I already ordered the OEM expensive one, but I ordered this cheap one too and I will test them and compare.

    https://www.ricambio.co.uk/products/radiator-fan-switch-fiat-punto-mk1-bravo-a-marea-ducato
    https://www.amazon.com/Thermo-Switch-Temperature-7745216-Fiat/dp/B09664XNMK


    On that note is there a thread or a list with a cross-reference of parts that are the same but affordable from other cars? Like this or the Porsche 911 throttle bodies, etc
     
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  9. Qavion

    Qavion F1 World Champ
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    #59 Qavion, May 15, 2025
  10. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #60 aventari, May 19, 2025
    Yeah I assumed the 'normally closed' thing is just amazon listings being stupid like they usually are... I was right haha

    I received the part $20 amazon part and tested it just now.

    I didn't see any temperature values so I tested with a oven thermometer:
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    These are the values I got:

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    Kinda high unfortunately. I will test the OEM $120 Ferrari switch when I get it in a few days.


    And I haven't tested that it properly plugs in yet or the thread size and pitch.
     
  11. aventari

    aventari Karting

    Dec 9, 2010
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    #61 aventari, May 19, 2025
    And just soldered the new temperature fuse on the resistor, assembly tests out good at 0.5 ohms now.

    I have a Porsche 944Spec race this weekend, but I'll try to install this in the next few days.


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  12. Qavion

    Qavion F1 World Champ
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    #62 Qavion, May 19, 2025
    Last edited: May 19, 2025
    I thought I tested my Ferrari temp switch and got the higher value on pins 2 & 3.

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    Unfortunately, I gave the switch away so I can't retest it.

    From the wiring diagrams:

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    The AN (blue/black) wire on the right side of the switch goes to the RH fan high speed relay's coil.

    Are the pin numbers marked on the cheaper switch?

    The wiring diagram graphic shows the harness connector from the rear (wire side), so it should correspond to the switch pin layout. My Ferrari switch had pin numbers embossed on the switch.
     
  13. Qavion

    Qavion F1 World Champ
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    #63 Qavion, May 19, 2025
    Here's a picture of an OEM Ferrari switch...

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    Pin numbers are shown on the sensor. The wiring diagrams, however, show letters, starting with A (ground) and, going anticlockwise, B & C.
     
  14. aventari

    aventari Karting

    Dec 9, 2010
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    #64 aventari, May 28, 2025
    I haven't had a chance to work on the Ferrari for a bit as I was racing as mentioned (me in the green one :D)

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    But today I was able to install the new temp switch and fixed resistor. Everything is fixed and finally working!



    So when I got the OEM switch from AWItalian last week, it wasn't in a Ferrari bag so I'm not exactly sure it was OEM. It was definitely $120 though.

    I tested the Amazon one again and the OEM one I got and they tested identical temperature values.

    Low speed opens ~197 and high speed ~209

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    Highly accurate and repeatable testing methodology

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    Amazon left, OEM right:

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    Amazon right, OEM left...
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    This is interesting.. I pulled the original sensor and it has a rubber oring. Both new sensors came with aluminum crush washers. I didn't have a new oring, but the old one was in good condition so I re-used that.

    You can also see the new Ferrari sensor is shorter than both the Amazon and the original OEM sensor. It was actually pretty difficult to thread into the radiator too.

    My conclusion is that next time I will save the $100 and go with a Fiat Punto sensor from Amazon..

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    Took it for a drive and everything is working

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  15. Qavion

    Qavion F1 World Champ
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    #65 Qavion, May 28, 2025
  16. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #66 aventari, May 29, 2025
    This is the AWItalian one, no numbers, no potting/epoxy like yours
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    Good eye on the wiring leads, I was not getting the high temp circuit to close so I was playing around with the leads trying to see if I had mixed something up.. ignore that :)
     
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  17. 360trev

    360trev F1 Rookie
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    #67 360trev, May 29, 2025
    Just to add further to this thread on interchangeable parts, sensors, actuators etc.

    Most of the 'conversions' from voltages or resistance are done within the ecu's using data tables, these are done for sensors directly connected to the ecu such as temperature or air flow meters, etc..

    It has what's known as a 'linearization', i.e. the mapping data which converts volts reading into a physical attribute like temperature that the ecu can use for its various checks and algorithms. This is the one I just dumped out of a 360 engine temperature sensor (as an example). Its used with interpolation so you can accurately detect the temperature to a millivolt to Degree's Celsius in this case.

    1) 0.25V : 143.25 Grad C
    2) 0.41V : 129.75 Grad C
    3) 0.51V : 120.00 Grad C
    4) 0.62V : 110.25 Grad C
    5) 0.78V : 99.75 Grad C
    6) 0.98V : 90.00 Grad C
    7) 1.23V : 80.25 Grad C
    8) 1.52V : 69.75 Grad C
    9) 1.88V : 60.00 Grad C
    10) 2.27V : 50.25 Grad C
    11) 2.70V : 39.75 Grad C
    12) 3.16V : 30.00 Grad C
    13) 3.57V : 20.25 Grad C
    14) 3.96V : 9.75 Grad C
    15) 4.28V : 0.00 Grad C
    16) 4.51V : -9.75 Grad C
    17) 4.71V : -20.25 Grad C
    18) 4.80V : -30.00 Grad C
    19) 4.88V : -39.75 Grad C
    20) 4.92V : -45.00 Grad C

    So, if you have a physical fit on say a temperature sensor but the mapping doesn't match (different physical attributes) you can adjust the linearization mapping data to suit the sensor. This ofcourse requires reflashing of the ecu but it does mean many more (less expensive) sensors can then be used on pretty much any engine. Manufacturers have been using this to ensure the most expensive sensors match up to the most expensive cars (a bit of a scam yes) but actually if you can adjust the conversion/mapping tables (which I can) the world opens up for much more cost effective sensors. As long as the range of temperatures is a good fit and mapping is done well it works just fine...
     
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  18. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #68 aventari, Jun 4, 2025
    Very interesting, I built my own Arduino sensor controller (https://github.com/aventari/arduino-ble-sensors) and have built and messed with early Megasquirt and instead of interpolated lookup tables have used the Steinhart-Hart equation for NTC thermistors https://www.useasydocs.com/theory/ntc.htm

    Probably just because it uses less memory.

    I love that you can just edit the lookup tables in the Ferrari FW to use any cheaper sensor :) I do need to get your FW upgrade soon... I also think my 50k mile throttle bodies may be not acting perfectly. Can FW detect that?


    For this radiator fan switch (not temp sensor) though it's all super old school, it doesn't involve the ECU at all, these switches just close at preset temps. The switch itself looks almost identical to the one in my 70's VW Scirocco.. It's crazy they dont have the ECU control it, but I suppose Ferrari would have had to add an NTC thermistor in the radiator to get the actual radiator temps and not the engine temps behind the thermostat
     
  19. benino

    benino Rookie

    Mar 6, 2025
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    #69 benino, Aug 4, 2025
    Gonna need a picture of that Scirocco :-]
     
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  20. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #70 aventari, Oct 26, 2025 at 10:17 PM
    Been driving the car a lot, it's been great! Super reliable and fun, the only thing mechanical I've done in the last 5 months is replace the radiator cap.

    Today I finally installed the interior back completely and wow is it a lot quieter with the rear panel carpet attached ;)
    Thanks for the help installing it @benino

    Also started the fiberglass repairs on the rear under tray. I will get some pics. I guess I never mentioned that I finished the front undertray to a decent standard. It works well.

    The rear one needed a lot more patches but I have a little more experience now and it's coming along well.

    My friend @benino picked up this 308 a month ago. We drove it from Oregon to San Diego


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  21. aventari

    aventari Karting

    Dec 9, 2010
    190
    San Diego
    #71 aventari, Oct 28, 2025 at 11:40 AM
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