Hi,
Well, no vac leaks from the breather pipes, they are spotless, I reset the ECU, no difference, checked the manifold nuts, throttle body screws, all perfect..
I sprayed carb cleaner at or around all of the air connections I could see, even the manifold where it goes onto the head, no rise in revs.
There's not much left for me to check!. It's at the stage now where, when the engine is hot, it will last 10 seconds or less before the revs rise and the EML goes on, switch off, restart, and 10 secs or less and it's away again
I think the Idle control valve could well be the next thing to look at. But wouldn't there be a fault code showing up for the ICV?.
No easy two screws to hold it in though, a big plastic body held on with 6 clips, underneath which I assume the ICV lurks? . So if I remove the TB then the plasic clips, can I then access the ICV and clean it? Or is this the cover for the fly by wire actuating assembly?
Thanks for all the replies folks.
Alan.

Oh dear, sods law has struck!. My missus used the car to go to the shops, a round trip of maybe 7 or 8 miles, came back and said, it's running great now!. What?.
So I went out to the car, fired it up, sat there for 15 minutes, runs perfectly!. Jeez, will I ever find what was/is wrong, cos it's likely to happen again lets face it!. Here's the sequence of events, it's acting up every 10 seconds, I clear the codes (only 0101)I let it cool down a bit,, maybe 15 minutes, I then start it and spray carb cleaner over the breather pipes, the inlet manifold where it joins the head, the throttle body area including the clipped plastic box on the end of the TB. and the MAP sensor area.
And now it runs fine????, which is of course just great, however, I would really like to know what's going on!.
Alan.

There could be a gasket problem. You have one that can give you that problem: the one under the throttle body.
Also, there are more gaskets, on every piece that goes into manifold and especially one gasket to each injector between manifold and rocker. Considering that your car is from 2017, I don't think those gaskets are worn out, but it is not impossible for them to be.
But the problem may be at that gasket under throttle body and chances are increased if you have taken tb down already. If the problem reocours, check that gasket and replace it if you need to.

Im with you on the probable Electrics fault and from personal experience with faults that repeatedly follow a certain pattern I have ordered a new ECU today, I know it seems a bit drastic but with 2 other Pandas (one I still have) after replacing many components to no avail the ECUs sorted them both out. The ECU.s are notorious for failing, like the power steering !! We will see when its fitted AND been ran for a while !!

I shall indeed ensure the TB gasket is sealing, but as you say, the car is only just over 3 years old, and this problem started first when the mileage was below 10K. Very strange.
KevinPanda, try spraying carb cleaner in the places I mentioned, easy and quick to do, I'll be interested to hear if you have the same results, although I can not imagine why this would solve the problem, it has to be coincidence. I'll be using the car tomorrow, I fully expect the fault to return.
Please do report back on the result of replacing the ECU, I'll be very interested to hear.
Alan.

Folks, don't forget the excellent services of ECUTESTING.Com, who will take the ECU and test it thoroughly and confirm any issues, and if necessary address (either by repair or exchange). I've used them twice before and they were very professional and efficient;

https://www.ecutesting.com/common-faults/fiat/

With next day Couriers so available these days, it might be worth a slight period of downtime on the car to get the ECU checked before spending the money on sa new one?!

I'll certainly keep that in mind Ringa.
As expected, the fault has returned!.
I'm going to check the throttle body gasket area, maybe spray some carb cleaner on it again, see what happens, at least then I would have isolated the area the fault might be in?.
Alan.

HHHMMM,
Sprayed the carb clean on, started it, after a minute or so, P0101 again, switch off, start again, spray carb clean on the TB, idles fine, maybe 10 minutes, I rev it a little, let it idle, 10 seconds and P0101 again..
I drove it today for maybe 20 miles, I noticed when changing down, just before I stop, the revs go to 500rpm, then up to 900RPM normal idle speed.
This is driving me bonkers.
Alan.

Bison
If I would have that problem, I would give it a try on changing the manifold gaskets.
They are not expensive at all, you find them on set and it has every gasket for all that goes into the manifold.
Identifying the leak with carb cleaner spray did not work because you had no leake while trying it. If the engine revs and you spray then, it will revv even more and help you to pin point the leak. But with the gaskets is tricky because you probably don't have a complete worn or torn gasket so that the leak to be always there and the spraying test to work anytime. With the moving vibrations the crack opens up and the problem arise.
And the code you get, to me, suggest the same thing: vacuum leak.

Hi Mike
I sprayed carb cleaner on the manifold joints when it was running, no change, and here the cheapest I can find the rubber gaskets is £18.90 each, so I would be spending £76 on four gaskets when I'm not sure it's the problem. Of course I may end up doing that anyway. I would have guessed if there was an air leak at the gasket it would have been worse when cold?, when everything is hot all would expand?.
I'm trying to get into an Italian fiat forum, I found a post with the same problem, 13 answers, but I'm having great difficulty login into it, can't find out why.
Thanks,
Alan.

What brand of new map sensor did you fit?

Bosch, exactly the same as the original. Do you think there's a bad batch?.
Alan.

Lot of problems caused by non branded /cheap sensors.
Glad you got bosch

For the revs to rise to 1500 rpm that would make me think it is a fair old air leak. You should be able to hear the hiss of air with a length of thin plastic tubing with one end close to your ear and the other as a probe. Could it be the brake servo or the piping? Listen in the exhaust for roughness too.

The leak is on something that is not permanently open. It only opens up when it revs by itself, you said it is random, not all the time. That is what I said about testing with carb cleaner spray. If you can catch the engine while it does the revs, then let it run and spray. I think that goes the same for the method presented by Murphy. If the engine does't rev to 1500 RPM, the problem is not there at that time so you cannot find it.
Another possible cause that I've thought that might be is the acceleration. You have an electrical one, with sensors, not on cable, don't you? Maybe there is some bad contact on the wires. Try cleaning them, including the part where wires go into the plug. But having the P0101 code, I guess it really is a vacuum leak problem, not an acceleration one.

With air leaks you get a pronounced chuffing in the exhaust tone.
Why I suggested the servo is I've had a diaphragm leak but it took a few minutes to show up. I'd take the pipe off the manifold and plug it even with your finger!!!

Hi Guys,
I'll try to explain.
It only happens when the engine is at proper operating temperature, and only at idle. It will idle perfectly, for sometimes a minute or so (the time period is getting shorter) sometimes 10 seconds, suddenly the EML goes on and at the same time the engine revs rise to 1500rpm and it is in limp mode, no throttle response, hill start not available etc etc. Going into limp mode was what made me think it was a sensor problem. Switch it off, immediately restart it, and it's fine, drives normally, stop at a set of traffic lights and the same thing happens. If you don't move, the lights take a long time to change lets say, you switch it off, restart, it idles fine right away, then 10 or 20 seconds later, away it goes again, eml on, revs rise to 1500 and it goes into limp mode, P0101, again and again. If it's cold, no problem, idles just fine.
If there's an idle bypass stepper motor on it, that would be a likely culprit, it's opening up for some reason when hot
The servo is a good thing to try, I should have thought of that. Although the brakes are great, hot or cold
Alan.

Mate, I really hope you get the fix of it sooner. I imagine how you must feel about kt. The brake servo really is a good thing to check saying that problem comes back when you STOP at red light. And the sensors if broken, don't usually just come back after a new start, the vacuum, while not pressing again what couses the leak (break) does come back. So good luck, hope that you fix it!

Hi.
The ICAV in my Rover 75 failed but it wasn't intermittent it just revved continually. In fact it was fixed by dismantling and cleaning with carb cleaner. You got a mis firing putt putt at the tail pipe. For it to do what you say I very much doubt its an air leak.
Check connections on the ECU, make sure the big connector is secure, all other leads are fully home etc. Disconnect the MAF and see if it revs and throws up the code quicker. Sounds like the issue is showing when the system is switching to closed loop.

Have a go at searching the forum using the search function for p0101 and p0106.

You would be well served by getting MES and a lead to connect and scan your car, I don't think you are getting the full codes and description you need to diagnose your problem.