I have to say, I did one this morning and it made a world of difference. No more erradic idle, no fuel smell from exhaust, and no more idle surge while sitting.
Glad to hear that, as I said previously, this procedure should be done couple times a year because the ECU's take too long to re-learn variations of sensors readings, specially if you don't drive your car often.
I would like to add this ... remember that these cars are old .... so ... Before starting the ECU's reset procedure and with the battery disconnected, clean accurately all the contacts, starting with the ECU's connectors behind the seats, MAFS and anything in the engine that has a connector. There are 4 connectors under the Air Filter box, absolutely don't forget those. Using a good fast drying contact cleaner, spray both sides and plug / unplug several times the connectors. Finally re-plug the battery and start the engine, radio, lights, fans must be all off. Don't ever touch the accelerator during the entire procedure and wait for the cooling fans to start .... and you are done. If during the entire procedure your engine is not steady idled or CEL ... then you really have a problem.
Indeed. While there is something to be said for the "Italian tune up", this is more akin to superstition rather than science. But, yes... If the contacts in the ECU connector are funky, d/c and r/c will provide some mild cleaning
Ok Brian, I believe that all of us should give you some credit, but you have only mentioned Tin foils, Loads ... and Placebos, while some other have posted simple resolved facts as "erradic idle", "surge", etc.... Shouldn't you also give these guys the benefit of the doubt? You could be wrong, you know? When everything else fails....even the guys at Microsoft have to reboot those O/S sometimes....
Better yet, for all those "re-setting" their ECU's, Bosch Technical Support has an 800#. Why don't you call them up, tell them what you are doing, the "results" you believe you are getting, and ask their opinion? After the Bosch Engineer on the other end of the line gets through laughing, maybe he will take the time to explain it to you.
All ECU's with memory (or any electronic device with memory, including your fancy coffee maker) can be reset --- and the memory cleared. The point is it won't affect how your car runs. It's just isolated, storage memory --- it's not executable / accessible data that has any influence over how the CPU processes anything.
David- Absolutely true, but I bet Roberto's cleaning of the connections provides a real benefit and that is what he is seeing. Note Ricambi now has the magic connector elixir for sale again. Brian- Is that connector stuff (Stabilant 22A) as good as I have heard? Should be good at $70/15 ml. http://www.ricambiamerica.com/product_info.php?products_id=261171 Taz Terry Phillips
Now... that I can say is completly wrong. And (Ferraris apart) I can provide two diferent examples (from my professional experience): 1-Bosch JTD Fiat management, is self learning in all of the rpm range. It builds itself a database and improves it self along the way. The goal is to improve the usage of the available computing capabilities. You can use the car on city traffic and it learns... you can use it on highway and it behaves completly diferent after a couple of hundred Kms. You reset it and you'll have an average performance. 2-Honda i-DSi engine managment. The learning process was beeing corrupted along the way by a small hardware problem (on a later recall group of cars). The glitch on the ECM motherboard was corrupting the learning process, giving problems due to degenerated management maps. If reseted, the engine performance would return to the starting point of the process. So, apart from the basic running program, both the idle setting parameters as well as self improvment maps can degenerate hence resulting in less than perfect running. The "return to basics" is allways possible. Again, I did not had the time to investigate about 348/355 specifications.... so I'll just guess that It may be possible too....
I wouldn't ever imagined that the opinion I have of any ECU problem could create these kind of comments and been laughed for it from mates who know much more than I do. I sincerely would like to apologize to everybody for any wrong advice I have given out.
Folks, Modern ECU's do "process" ongoing real-time data, and they do make trim adjustments (aka, "learning" and input-specific adaptation), but all of this is still within normal range of operational parameters. If the car is exhibiting faults and poor running condition, this is outside of all that. And, it is endemic of a different type of problem. If you clear the ECU memory, and the symptom seems to go away, it is only an anomaly --- the problem WILL reappear. When you are "re-setting" the ECU by d/c//r/c, you are also interrupting and re-establishing system level electrical grounding --- and this is what has the effect. It also means there is a ground fault somewhere in the system --- nothing wrong with ECU or what it "does". I don't deny you may see a real change with the ECU d/c//r/c, but I assure you that it is not fixing the underlying problem
Terry: You may want to perform a search regarding Dave Helms' comments on the use of Stabilant-22 and build-up of "fiber-like" deposits on contacts. I too, previously, was a proponent of Stabilant, but after talking to Dave and seeing the results of its use on contacts, I was convinced that it actually causes problems rather than preventing them. I used Stabilant on my MAS (as directed) the last time I cleaned it with CRC MAS cleaner. Subsequently, on the next MAS cleaning, when I went to check the electrical connection, I did notice fine, white fiber-like deposits on the contacts. Thus, no more Stabilant and I am about to begin installing Dave's Gold Connector kit. As Dave has stated, all high performance contracts are manufactured from Gold and are assembled in a "dry" (i.e., no contact enhancer) manner. Just my two cents.
Especially when they were writing the manual. I posted this in another thread, but what the heck here it is again. Here read for yourselves what the FACTORY wrote, while they had their tinfoil hats on. Pay particular attention to the last bits of what the factory tinfoil hat brigade wrote, it has a nice "placebo" effect. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
So yes, resetting the ecu's DOES have an effect. And NO it's not a "placebo". Which is why the original poster noticed a better idle after the rest. The factory manual even says so. But hey what do I know? I'm only a Stooge. Now where did I put my tinfoil hat? Image Unavailable, Please Login
^^^^ Yes but the ecu still has full ability to constantly learn/adjust any learned values without disconnecting the battery. Even if you disconnect the battery and zero out all learned values they should soon return to the same learned values it had prior to erasing them as nothing with the car has changed. For example, lets say you've been driving the car a while and the short term fuel trims drove the long term fuel trims to +7% on both banks. You disconnect battery and wipe out the learned values, start the car and STFT's and LTFT's are at zero. STFT's would quickly bring long terms back to +7%, as they were. I guess I'm just really failing to see what a battery disconnect accomplishes as it isn't enabling any features that aren't all ready operational every time the car is ran.
Where would be the fun in that? I can say what aircraft mechanics do on modern aircraft when they can't reset a system's computer. They de-power the entire aircraft and turn off the battery (some call it a global reset). A reset of the Motronic may not help a perfectly functioning computer but it's worth a shot on a transient fault. In fact, the battery is off in our Mondial 3.4 right now. No tin hat required. Dave
This is true. I found this out years ago after being one of the first to start the S22 bandwagon. Sorry about that guys. I found S22 not doing it's job when I was racing the 348 and doing connector disconnects yearly for my yearly engine out service because of racing. I found s22 worked awesome miracles at first but the effects soon wore off. While this was a milspec military creation I'm sure it works but not for our application. I may have seen bad effects early because I used s22 not the thinned out s22A with alcohol. So toward the later years of my 348 I just cleaned connectors every year with contact cleaner and assembled them dry. That actually worked more consisently than s22. Now I have experimented with Dave's gold connectors and wow! I'll say more positive things about that in the future.
