Engine cut off oddness - Any ideas chaps?

David, I'm not sure about the problem but you don't need lead replacement additive as these engines have hardened valve seats as standard. Have you used this additive in the car before today ?

Which fuel did you use ? I've been advised by a ferrari engine builder that either Shell V-Power or Tesco "whatever it's called" are preferable.

It is hot today - is the engine running hot or at normal temp of 90 degrees approx ?

 

With that symptom, the first suspect to rule in, or out, is the mechanical advance mechanism in the distributor -- has it been serviced/checked within the last decade or so?

JMO -- Good Hunting!

 

David, I believe that the Dinoplex has a rev limiter. Is it possible that the rev limiter is failing?

Tony

 

I'm certainly not an expert on V-12 Ferrari motors, but generally load just implies that you're using more air and gasoline. For the engine to be cutting out, one of these ingredients must be missing in pretty significant fashion.

 

I would have to agree. I'm not sure the service procedure on a V12 Ferrari, but I would check the carburetors for function and fuel delivery, however that is done.


Years ago, I had a Wankel Rotary powered car with a similar symptom. The 4 Barrel Carburetor was not delivering adequate fuel from a gummed up jet in the secondaries. The power would taper off around half way through the rev band.

 

I doubt that the additive is the cause of the problem, just thought it best to tell you that it wasn't required.

That said, different brands of additive have different chemical formulation and these shouldn't be mixed - was the additive you used on both fill ups the one that came with the car or the one you use in your TR (or are they both the same brand and variant ?)

And about the "bloody car" comment - my friend get used to it cos its a Ferrari !

 

If it's a "water-removing" additive (i.e., with methanol), I've heard that can be trouble for CIS fuel distributors -- what general "type" additive is it?

 

So, this car is Bosch K-Jet injected, not carbureted, but I would tend to agree that fuel delivery may be a culprit. The distributor is basically a control plunger and it rarely malfunctions "partially" the way this one is. The sensor plates associated with the plungers under the intake boot may be gummed up, a quick carb cleaner burst used to work on my old BMW. Similarly, the injectors themselves may be obstructed. They must be removed to be cleaned. The fuel filter(s?) also accumulate debris and can choke an engine out. Ultimately, a check of the fuel pump itself may be necessary.


If the symptom was occurring when cold I would also suspect the WUR filter, but the OP stated clearly that he warmed for 15 minutes prior to driving.

 

My guess would be a clogged fuel filter. It lets some but not enough fuel pass. Just my .02

Geffen

 

You'd have to be more specific -- Wynns makes a product called "Dry Fuel" that I'd be leery of using, but some of the other "injector cleaner" types are probably OKish.

Can you be a little more specific about your trouble:

Was the car running perfectly, and, all of a sudden, this problem appeared?

or

It's never been quite right during your (brief?) Ownership?

 

I didn't realize this was an injected engine. Might there be a troubleshooting tree in the service manual for such a problem?

 

This is the curse of the 3-speed auto box of the day. I know exactly what you mean BUT the car is such a pleasure to drive with the auto box I enjoy it for what it was designed to be - a gentlemans express. Totally different driving experience to a manual and one that I accept as part of the cars character.

Agreed

Are we talking the car in general or fuel capacity ?

 

fwiw, i'm going with Digiplex or coil...with the hesitation prior to cut off possibly pointing to distributor.
but, obviously, it has to be something that is causing you to lose the whole motor...the car has two fuel distributors, but only one dizzy, one coil, one Digi...good luck.

 

I've had a similar problem and it was fuel starvation- Rebuilt fuel distributors and all better.

I've always found the hard stumble under acceleration to be fuel rather than spark or timing.

 

Jay, this reminds me that I need to head out your way for a drive. My car isnt pulling well at high rpm and I want to compare it side-by side to a sorted 5spd.

 

Yeah anytime- Both cars are running great!

 

As Santos first mentioned, too little fuel or air flow. Several mentioned fuel filter since it is very likely but clogged air filters will give similar result. 80/20 for the fuel filters.
Ken

 

I wouldn't mess with the mixture control screw on the distributor before checking all other possibilities, but it could be as simple as running lean at WOT, which a 1/4-1/2 turn on the 3mm(?) hex screw could remedy.

Once again, would NOT try messing with FD settings before determining that you have no other disruptions in fuel and air. Best bet before changing the FD settings is to actually tap a pressure gauge into the line and check your system pressure under different load conditions.

 

hey Jay,

then why the backfires at the same specific moment/rpm ?

so he's got fine fuel delivery up to that specific moment and then the independent fuel delivery on both sides of the motor do exactly the same thing ?

I think the backfires are caused by the fact that ignition is no longer occurring at the right time...

I like what Oldcoin had to say, with the exception that the rev limiter in the Dinolex would not know whether it was under load or not...it's just an rpm based signal/trigger.

again, good luck...keep us posted !

 

+1 -- Didn't someone once say that 90% of all carb/injection problems are ignition-related?

I wish the OP would answer whether it ever worked right, or not -- if it hasn't, another thing that could cause this specific symptom would be the dist rotor position relative to the cap/housing not being set correctly (the width of the 400i dist rotor is not generous).

 

Have you checked the petrol pump relays yet ?

Jerry