TR low idle

The normal idle speed for a TR is 1,000 rpm +/- 100 rpm. If your idling at 1,000 rpm that is about right? Can you go into more detail as to what's happening? Does the car just die, does it cough and spit.....

More information is needed...

 

Ditto:

1. Is this a "new" problem that just suddenly occurred?

2. US version engine family F113A040? (or give engine family)

3. Do you mean that it idles OKish at ~1000 RPM, but, when coming to a stop, the RPM undershoots to ~500 RPM and sometimes recovers to 1000 RPM and sometimes stalls, or

it idles at ~1000 RPM (when stopped) and just sometimes stalls from there?

 

I can't recall anyone else reporting a similar problem of "warm idle OK when stopped and then just dies" so you're in new territory (lucky you ).

The TR engine family is marked on top of the engine block at cyl #6 as shown in the jpeg -- please check:
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I have no idea if it's relevant to 12 cyl TR's, but 8 cyl 348's will die when the car stops moving if our idle air bypass valves aren't open enough.

 

Thanks -- based on your location, I probably could've just assumed that you have a US version TR, but it helps me to know for sure. The translations for your markings are:

5.0L = engine displacement
Ferrari = engine manufacturer
F113A040 = engine family = a US version TR in this case
14502 = engine serial number = the unique engine SN assigned to your particular F113A040 engine assembly

The good news is being a US TR, we know it well; the bad news is your problem isn't a common one, and being "cured" by just restarting seems to imply that it's a very intermittent fault that will be hard to "capture". There are many places in both the ignition and injection systems where a single momentary electrical glitch could cause a well-idling US TR engine to stall, but, if it always is OK on restarting, I really don't have any easy advice for you on what to check.

One thing you could try (if the failure is occurring fairly frequently) is unplugging the single wires of your O2 sensors, and operating the system as a KE-Jet without Lambda (but don't flog the heck out of it) -- if the failure went away in this configuration, this would be a clue that there's something wrong in the Lambda stuff and the ignition is OK. However, I'd say it's just as likely that you're momentarily losing the ignition. If you get more information, or if the symptom changes or gets more frequent/consistent give a shout.

 

There are two O2 sensors -- one is mounted in the exit area of each cat. The wires and connections are on the RH side of the clutch housing between the clutch housing and the 1-6 distributor cap. Each O2 sensor has a single wire with a single spade connector (this is the actual O2 sensor signal) and a double wire with a 2-pin molded connector (these wires run the internal heater so just leave them plugged in). Label things so you don't mix them up after unplugging/replugging.

A US version TR has a KE-Jet with Lambda injection system where (when warm and not at WOT) the injection ECUs use the signal outputs from the O2 sensors in the exhaust stream to fine tune how much fuel is provided. The later euro TRs (F113B) have a KE-Jet without Lambda injection system that does not have O2 sensors and does not have this fine-tuning ability. When you unplug the signal wires of the O2 sensors on a US TR, the system defaults into working like the (more simple) euro system (so if the problem goes away, you can concluded that it has something to do with the "Lambda" stuff -- like the O2 sensor or the injection ECU itself).

 

I don't mean to butt into this conversation or be rude.....but....

Your picture shows one of the thermocouples (there left and right ones) and not the O2 sensors. The thermocouples only read exhaust system temperatures and if things are too hot, it trips a warning light in the dash instrument cluster.

Unless my eyes are playing tricks on me, the picture seems to show some type of aftermarket exhaust system and not the original one? So you may not even have catalytic convertors installed, but bypass pipes instead - which is okay.

As our Testarossa expert "91tr" has pointed out, look at the passenger's side of the clutch bell housing area at the rear of the engine, you should see 2 groups of wires (3 wires in each group) running down to the O2 sensors. There is a 2-wire connector and a single wire connector for each O2 sensor. You are after the single wire connectors, mark them before disconnecting so you don't accidentally switch them around later.

So take another look and let us know what's going on......

 

The thermocouples are items 53 and 54 in this jpeg and the O2 sensors are items 1 and 2
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Thermocouples turn heat into electricity. This is useful for telling a computer if your catalytic converters are overheating.

O2 sensors turn Oxygen into electricity (or resistance). This is useful for telling a computer if your engine is running rich or lean.