Motronic 2.7 junkies, come out and play !

check your plugs on that bank for fouling. Had a fouled plug in my 355 and did exactly what yours did....caused unburnt fuel into the cats which heated it up enough for the slow down light and ran very very rough. Changed plugs and viola! I hadn't changed plugs for 2 years prior to that.

JD

 

Senore JRR,

Since Luigi cannota make elctronic circuits worka. He decided to makea two of everythinga. So a quick diagnosis when you havea fried parta somewherea is to swtich the left coil to the right and see what happens. Then try the lefta ignitor to the righta ans so on... Also, I was one of the biggest proponants of Stablaint 22. I have since gave it up as I could really not prove increased reliability with the product. So I have just tried to keep connectors clean. So its crc spray and let dry for me but do it often make a huge difference in how well the car runs. Its part of a routine like checking tire pressures. Also to do your tests disconnect the exhaust ECU's. I run without thee but others like them for the obvious reason. But they do nothing but FU your ability to diagnose a problem. When someone report your kind of problem the first thing I do is disconect those ecus.

 

Oh...also water leftin a spark plug hole can cause arching and symptoms of misfire

 

Are you sure that the unknown material isn't a dielectric grease that was added in a prior "repair/restoration" attempt? Not sure that that would be my choice on that style of connector (wouldn't hurt maybe, but wouldn't really help either if the real problem is at the connector mating interface rather than outside contamination causing corrison) -- but just wanted to point out that the area might have been visited earlier by another. How are the contacts themselves -- any material discoloration or relaxation apparent? Your photo of the "good" side looks good -- the plating looks in decent shape and the female "tongs" still have enough preload to be fully closed. Those are the same characteristics that you'd want to confirm/deny on the problem side and at the male pins.

 

The only thing I can think of is that, maybe the past times that you washed the engine caused some water, dirt, grime, or what ever to get in there. Then as the current from the alternator was going to the coil it baked the stuff over and over and over. The connection kept getting worse and worse causing the spark to get stronger and stronger, which is why you see the burn marks. Electricity travels on the outside of the wire not the inside. If the path around the outside of the wire makes it hard for the current to pass it will look for the easiest way. Think of it as water building up. At some point the water will over flow. Well that over flow is the spark build up, that makes the spark jump to an easier path. That jump will cause the misfire. You will also want to you under the rubber boot on the back of the connector. Make sure that the wires and the back of the little clips aren't frayed, or broken. That will also cause the car to misfire. Either that or you do have a coil that is on the way out.

As Billbob pointed out you may want to try swap things from side to side. But before you do that make sure that everything is good and clean. Only do one thing at a time when you do swap stuff.

As Jeff said, I would also pull the spark plugs. About a year ago when I was having my problem, mine turned out to be okay. I reindexed the plugs to spec and put them back in.

 

That is exactly what I thought "dielectric grease that was added in a prior repair attempt"

 

Seems you have not following the Six Laws of Italian Sports Cars.

As the owner of an Italian vehicle, you have undoubtedly found that, from time to time, the thing defies all known laws of Physics. Distinguished researchers from all over the world have spent entire lives trying to understand such phenomena. Recently, the Six Laws of Italian Sports Cars were discovered, thus reducing most owners' dependency on sorcerers and prayer, to keep such cars running.

Careless application of these laws to any individual auto may fix the problems of the moment, but cause hives or allergies in said owners.


1) THE LAW OF PLEASING DESIGN WHERE IT REALLY DOESN'T MATTER "The inside of cam covers or other relatively innocuous areas, shall be laced with buttresses, cross-bracing and all manner of esoteric stiffness-with-lightness design, while something like connecting rods shall self-destruct at redline plus 1.0 rpm due to a basic lack of strength." An example of this Law is the stunningly beautiful Lamborghini or Ferrari V-12's of the late '60's. They were famous for wearing out all four camshafts in 10,000 miles or less. The cam's metal appeared to be recycled coat hangers, which coincidentally are still in short supply in Italy.


2) THE LAW OF NON-FUNCTIONAL APPARATUS
"All Italian Sports Cars, regardless of age, shall have at least one system or component which does not work, and cannot be repaired. Such a part shall never be mentioned in the Official Shop Manual, although there may be an out-of-focus picture shown." It goes without saying that such parts should never under any circumstances be removed, lest the natural balance of the car be upset.


3)THE LAW OF ELECTRICAL CHAOS
"All Italian Sports Cars shall be wired at the Factory by a cross-eyed, color-blind worker, using whatever supplies are within reach. All wires shall change color-code at least once between energy source and component. all grounds shall be partially insulated." This tends to guarantee that the owner of such vehicles will eventually be intimately familiar with its electrical system, since he will need to trace out each wire, then rewrite his Official Schematic, which will differ from all others in at least one area.


4)THE LAW OF PERSONAL ABUSE
"The more an Italian auto breaks down, the more endearing it becomes to its increasingly irrational owner." For example, you purchase an Italian Sports car, for all the money you ever hoped to earn, and receive a ticket for air pollution on the way home from the dealer due to the vast clouds of smoke that follow you. Several return trips to said dealer, accompanied by your rapidly dwindling cash reserves, cures the smoking. But now, the engine sounds like a food processor full of ball-bearings. After replacing every component in the car, including the radio speakers, the noise vanishes and is replaced by an odor reminiscent of a major fire in a goat-hair mattress factory. You still keep trying, God help you.


5)THE LAW OF UNAVAILABLE PARTS
"All parts of an Italian sports car shall be made of a material that is available in inverse proportion to its operating half-life." Thus, the speedometer hold-down screws are made of grade 8 cold rolled steel, while the valves are of fabricated Unobtanium, made only at midnight by an old man with a pointy hat covered with moons and stars. Such parts will be backordered during the design phase of the car, and will remain so forever. Bribes, pleading and threats will be ignored.


6)THE LAW OF CRYPTIC INSTRUCTIONS
"Any official publications dealing with repair, maintenance or operations of an Italian sports car, shall be written such that every fourth word is incomprehensible to the average American. In the event that a random sentence is understandable, its information shall be wrong." This is also known as flat-tire English, where a sentence flows along nicely, then-Kaboom!

 

ROFL!!!

The only thing missing is the dialogue describing Lucas electrics. Heaven only knows what we did to deserve Italian cars with Lucas electrics, but it happened to some of us.

Remember the golden rules of Lucas auto-electrics: The aim is to keep the smoke IN the wires and other electric apparati. Should the smoke leak out - you have a problem.

Dave

 

"clean as a babies butt"? I've seen some nasty babies's butts. sorry about that I couldn't resist. Anyway, when I owned my 348SS I had the common problem with those damn temp. probes malfuctioning they would shut down the injectors for no aparent reason. I removed them and never had anymore problems with the engine in the 20,000 miles and 7 years I owned the car. I now have a 355C (97 with 2.7) that I drive on the street one of the first things I did was remove those probes. I have not had any problems with it either. I'm not saying that is your problem but the comment came up so I thought I would throw in my opinion. It sounds like a water problem somewhere spark plug, coil etc.

 

If the power modules and coils are the same on both sides, why not try some swapping around of those components to see if a bad player can be identified -- just a thought...

 

No!

 

Forgive me if I missed it, but...
what is the MIL code?

BTW, I agree, not the phase sensor. The engine will run quite well without this signal. It's there to verify crank position.

Best regards,

Rob

 

Rob pardon me for disagreeing on your answer but the engine won't run if crank sensors are disconnected at least mine wouldn't. The signal the ECU uses from those sensors is for ignition and fuel injection timing.

To answer your question JRR on the temp probes you are correct we are on the same page cat probes/ecu/temp sensors etc. Also as was said before switch parts around one nice thing about Ferrari is that there are two systems on these cars one for each side works great for trouble shooting.
Have you checked the fault codes on engine manegement ECUs. Also coils can malfucntion. I have not personally had one do it but have seen it before.
If you do not have the work shop manual chart on the break down of the codes let me know I could fax a copy to you, but that is where I would start.

 

Not quite Vern...Rexrcr is correct Phase sensor is for cam position and car can run and start without it. You are correct TDC sensors are mission critical. There were just reading the post too quickly errors. Hey how is the water in Montana? Are the rivers looking good and the snow pack normal?

 

I was focusing on Rexrcr's "crank sensor" part of his post I guess he meant cam shaft postion?, your correct on the "phase sensor". Anywho alls well.
OK now what does snow pack in the Big Sky State have to do with sensors on ferraris. HaHaHa. We have been dry this year but we get a lot of snow in the mountains in May so things are looking a little better. I'm not sure what southern MT is like (Bozeman/Livingston area) were the best fly fishing is. I think this is where we're supposed to apologize for takin' this thread stage right ,so I am

 

MIL = Malfunction Indicator Light

It means that one of the check engine lights in the dash is out. I had this happen to my car. What is funny is that you will never know about that code unless you have it hooked up to a code puller. If you try to pull the code the normal way, you never get it because you won't be able to see the code flashes. Leave it to the Italians to have you pull a code for a burned out light, trying to use the light that is burned out to get the code. LOL

 

Glad to see you got it figured out Daniel.

 

Vern, if you re-read my post, it says "verify crank position." The phase sensor let's the computer verify TDC power stroke, vs. TDC exhaust stroke.

Best regards,

Rob Schermerhorn