355 Replacement slow down cat ECU prototype

I thought Goth originally had both types of ECU (one for faking, one for real).

If you want a cheap fake, try wbt's earlier fix (the diode and resistor method)... It works on the F355 2.7, but I haven't done any long term testing on the 5.2

https://www.ferrarichat.com/forum/threads/simple-2-7-slow-down-ecu-replacement-only-for-no-cats.538719/

 

Thread update.
355 360 456 550 575 cat ECU version is now complete, tested and ready to go, see image below.

Next projects:
355 bypass position dummy load prototype and testing (volunteers anyone?)
348 Cat ECU proto and testing (and an after market version of the now impossible to source connector)

In the more distant future:
328 Cat ECU
Keyless entry system to retro fit into 430 key with buttons. (FOB electronics repackaged)

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When will you be ready for mass production?

For people with their valves wired open?

 

I can make about 10 ECU's per week with my current workload (unfortunately I have a real job too, as much as I would love to tinker with these cars full time). I'm not quite sure if this constitutes mass production but it should be enough to keep the indy and DIY market in supply. I need to talk to the mods about sponsorship so I can post a sale link to my very new website.

355 bypass - yes for wired open valves and those who have de-catted and want to remove the entire centre position ECU/thermocouple system. The really big problem is finding a level that fools the temperature to look normal, but avoids a check engine light for a stuck valve. Without access to a 5.2 355 I don't want to sell a promise I can't keep. Bypassing the left/right positions is a piece of cake as I have detailed in a previous thread.

 

I would be happy to volunteer, currently have a 1998 F355 with secondary bypass cats removed and valve wired open

 

So Just to clarify, Is this for vehicles with the cats Removed?
Or is it, as I hope, a replacement for the oem ecu that is a bit smarter and doesn't give Faulse slow down lights?
if its the second option I soooo want one! for my 456
If so are there two or just one in the car and How much are they

 

To answer your questions in order...

It is both for cars with cats removed, or for cars with cats. I have 2 different solutions to 1) bypass unit to completely eliminate SDL ECU and thermocouples for de-catted cars, and 2) I have also designed a completely new solution for the OEM ECU with more modern componentry which is more reliable and eliminates false slow down lights (assuming the thermocouples are ok). I have detailed quite a bit of info about functionality on my blog https://technistrada.com/content/7-ferrari-slow-down-light-explained

Most cars have 2 ECU's but some have 3.

 

The black TCUs were replace on my 95 in 2006 1t 11 years, 14K miles. The green replacement are now 13 years old, 15k miles on them. So in my case we have an original design of which one failed after 11 years in a hostile environment and 2 replacement units which have gone 13 years so far in that same hostile environment. And I sure there are cars running around with the original units still functional afte 20-25 years. My last TV lasted 7 years before it failed. So I'm a little reluctant to consider the OE units as unreliable and without field testing I'd be cautious about claiming these new units as more reliable. They appear functionally equivalent and less expensive which is a good thing. But their reliability is too be seen.

Is there any warranty on these new units?

 

To be more specific around the issues of reliability, the factory unit is of a slightly questionable design electrically, with a very basic single op amp gate doing the signal conditioning of the thermocouple. It's an ok solution but not great and a known result of this type of design is electrical noise susceptibility and drift which could cause false slow down lights. I've tested both designs in an EMC chamber and at 10v/m my design output level is rock solid but the vescovini does wobble around a bit I suspect due to poor common mode noise rejection. Essentially it's still using 70'/80's integrated circuit technology where today we have some very good components available to condition thermocouple signals.
Lifetime testing has also been done using HALT techniques, with no failure recorded.

 

Thanks for the reply. Don't take my comments wrong. I'm just the pragmatic type. I applaud your efforts overall. So with the HALT testing I presume you looked at temperature extremes, vibration and on/off cycling?

I am still of the opinion that a component that lasts 10 years, or more, years isn't exactly unreliable, but that is just my opinion. To me the real problem is the cost of a replacement. And I have not had any occurrences of false SDLs, though I did have a true SDL due to a misfire and raw fuel in the cat.

But you didn't answer my last question, any warranty on the product?

 

Yes, my HALT testing was fairly standard process, heat cycled in a chamber while fixed to a vibrating platform, power supply was fixed but injected with ESD from time to time. Given it's a potted fully analogue circuit I wasn't expecting too many gremlins to pop up.

I expect each box to give years of service and there is warranty of one year. If something happens outside the warranty it's also very likely to be sorted out if I'm satisfied it's been installed correctly.

 

Please let us 348 guys know when our version is available. I can confirm at one sale.

 

Thanks for the reply. Seems like a great option for those who need them. Hopefully I won't be needing one any time soon.

 

Great service from WBT and well made SDL bypass units. I don't currently have CATs so these were perfect for me. I have had intermittent SDL problems so I suspect one of my ECUs is kaput. Anyway, now sans cats and the plug and play units were exactly that. Arrived in Blighty in <5 days.

 

Hi, seems like this might be the culprit of our Motronic 2.7 that causes random loss of power , 5-8 slow down light comes up and then it clears it self. Also this problem does show up in cold starts randomly as well? Sometimes the car won't start at all after few tries (injectors are cleaned and tested and are good, spark plugs new, sprak plug wires new, serviced, coolant temp sensors cleaned, wiring harness/DME claned , etc etc).

Are these available to buy? price each?

Thanks

 

How long have you been running this set up? Have you had any "check engine" lights related to fuel trims? I worked with my local dealer several years ago on installing a switch for the bypass valve (always open), as well as spoofing the 5.2 Motronic not to set a "check engine" light with the valve constantly open. They were able to spoof the Motronic, but said during testing and driving, so much exhaust was going through the bypass, and not enough past the pre cat O2 sensors, it was messing with the fuel trims and tripping the CE light. The likely thing to do, would be to move the pre catalyst O2 bungs to the merge collectors on the exhaust manifolds, but I told them not to bother and they ended the project.

 

I've been running it for about 2 months, I drive the car about 3-4 times a week and usually get a check engine light that only shows the bypass thermocouple code about 1 in every 4-5 drives. I clear it and it's good for another week before it pops up again, so it's not something that happens every drive. I have not had any other codes or SDL indicating a fuel trims issue or warning.

 

If your scanner can read fuel trims, you might take a look sometime

 

Yes, I've logged stft and ltft before and after and haven't had any major fluctuations in either especially long term fuel trim. What were you seeing +/- for ST and LT?

 

That's great then. I don't recall the actual figures quoted to me. If you are running good, then nothing to do.

 

I would like to know the voltage level that spoofs the central position cat on 5.2 cars and avoids a check engine light! I know it's definitely possible as others have done it - if someone has a working example and can trace the voltage please let me know so I can get these things available to the community. Cost will be less than $20 if it's for a bypass only without any thermocouple inputs.

 

I think I found the "obsolete" 6-Way connector for the early TCU 142581. It appears that 12052848 Delphi Metri-Pack 150 Series can be used but needs to be verified. The only difference I see, compared to the TCU 142581 connector, is that the step on the part of the connector that goes in is somewhat differently positioned on the Delphi - the step is positioned, from centre, a bit towards the wider section whereas on the original connector it is the other way around but I believe the Delphi will plug-in to the existing Ferrari harness connector (male). Anyhow, the matching male Delphi connector is also available from the same supplier. The Delphi connectors also have provision for the white plastic locking pin.

Delphi Female:
https://www.electricalhub.com/delphi-12052848-150-series-metri-pack-connector
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Delphi Male:
https://www.electricalhub.com/delphi-12124107-150-series-metri-pack-connector
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The locking pin for the TCU 142581 connector:
https://www.eficonnection.com/home/product/delphi-gray-metri-pack-150-cpa

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I can verify that the dummy load simulators he created work just as advertised. If you have no catalysts you can put these on and SDL is gone. First time in 8 years I have not had the light coming on and blinking at me every drive.