Slow Down??

Per other thread, scan OBD codes and report back. First level of diagnostics

 

That or we can figure it out at Stoogefest 5/21/16. All the cool kids should be there.

 

Hit the FOB first, key forward then scan.

 

Just use the "other"option

 

Oh boy. This could be fun to watch. Could be the start of another "girls gone wild" thread.

By the way, has your car had the OBD II connector update completed?

 

I keep seeing a "Slow Down!" warning when I'm in My 348 - It illuminates at the side of the road just before I enter a 40mph limited village from a 60mph limit road!

Braking or lifting off the throttle does extinguish the sign though in My case!

 

I resolved the converter temp & ECU issues in my 348 by fitting new thermocouples from Dr. Bob and cleaning all of the electrical connections with DeOxit. So far, so good, even though it looked for a while as though one of the thermocouple ECUs was going to need replacement.

 

+1

 

The is a common issue and usually pretty easy to trace. Most of the time, it's a bad TCU. Swap them side to side and see if your code moves. Thermocouples can go bad but in 90+ % of the cases, it's the CAT ECU (TCU).

I've been though this and resolved it by finding the offending TCU and replacing it. Problem solved.

 

I wouldn't be surprised if there are many occasions when TCUs are replaced where the real problem was just a bad connection.

 

Mistaken fact quote.

Show statistics to back up your 90% statement. You don't know that and stating such does not make it factual. It is not.

 

Very true, Mike. But those TCU's are a very long term, known issue. Luke recently had one dead bank and I advised him to get a new TCU from Ricambi and BOOM - car is running again

 

Yeah problem was with the silicon seals on the ecus. At my major service two years ago I told them I could try to reseal them but the mechs all said it was chasing the problem and could reoccur. The 355 vintage with green silicon were superior and the ugraded solution. It was "one and done" and I haven't had the problem since, except maybe once. Knock on wood. I just fixed my front bumper and working on a side marker light

 

I'm with you there, Dr. Bob. I too find those "statistics" puzzling. The last six F355/360s that came into my shop with slow-down lights had issues that were not related to the SDECUs. Despite the perceived commonality of the problem/solution, to assume that's it's a component versus doing a proper diagnosis is not helping anyone. Frankly, a misdiagnosed Slow down light, left unattended, can result in the loss of a car due to fire.

 

Can you expound on what those problems were so as to enlighten us for what to look for should we encounter a similar issue?

 

The first clue in the diagnosis is when a SDL happens at cold start - that is a dead giveaway that a it's not a true problem (over heated CAT). I'm not going to build a spreadsheet of statistics for the few disbelievers. Do a search on fchat and one will find the common (known) problems of the TCU. My only agenda is providing help to the folks in needed. I have first hand experience with this and have helped others with the same diagnosis that resulted in the same successful fix. Swapping of components is a nice easy method to sorting the problem.

 

BTW, I would like to add that the person who guided me most through my initial problem was Dave Helms and his experience was good enough for me. The first thing he said to me was "Does the light come on when the car is cold?" The next was, "Have a look at your TCU's and let me know what color the potting is"

 

You're the one quoting statistics that you made up with no factual basis behind them.

My personal experience with this problem in my car led me to the level of understanding that I have on it and how I guide people to figuring it out. In my case and many others it was a faulty thermocouple. Part replaced, end of story.

The SDECUs are definitely an issue but not the only one.

With an intermittent SDL you don't always see a code on an OBD scan associated with it. I had no codes or CEL and others I have worked with have found the same.