I just taken the panda for it's mot and during the smoke test the examiner commented the governed engine speed is too high, does anyone know how to adjust this as the local dealership wants £138+vat to do a diagnostic before they will adjust the maximum revs which they will charge extra for.
Any help would be much appreciated. Brian.

I cant help with adjustment, but my engine ticks over hot or cold at 800rpm

I guess that he must mean max rpm, they will definitely rev to 5000

Yes he does mean max revs not tickover.
The only reason he mentioned it was because he had just rebuilt a corsa engine and that didn't rev as high during the smoke test.
I think the engine may not have been hot enough the first time he did the smoke test causing the emmisions to be higher as having left it running for the rest of the test it passed straight away the second time.

It doesn't surprise me that a Fiat would rev higher than a Vauxhall, Italians will always sacrifice longevity for a bit of extra performance

floatinglandrover said:

Yes he does mean max revs not tickover.
The only reason he mentioned it was because he had just rebuilt a corsa engine and that didn't rev as high during the smoke test.

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Maybe the Corsa was not revving as high as it was supposed to do...

blod65 said:

Maybe the Corsa was not revving as high as it was supposed to do...

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:yeahthat:

So what exactly is the issue? Are they refusing to MOT it?

If so take it elsewhere.

i have had revs of 5600rpm on my engine.. because a friend wanted to try and reved it like a petrol... so thats posible..

The Corsa engine, like the Suzuki and the Ka are Fiat engines

Anyway, who cares what the engine can rev to, only an idiot would take it over 4000. There's no point as power drops off very quickly, I had problems with the gearbox slipping out of fifth into neutral (since repaired), that's how I know that 5000 is easily achievable. An MOT tester should take the engine to its max revs, he's not testing rev limiters.

The maximum power of the diesel engine is at 4,000 rpm.

While I would not recommend continuous running at maximum power I think it a gross overstatement to say "only an idiot would rev over 4,000 rpm"

With a thoroughly warmed engine and the right road conditions I would argue that a thirty second thrash with full throttle and 4,000rpm (and maybe a little more) would do the engine good as it would clear out carbon and exercise the turbo wastegate which will seize shut if the car is constantly driven easily.

It's called an Italian tune-up

The problem is only an issue during the mot as they have to floor the accelerator in neutral .
It failed the smoke test the first time as the inspector followed the on screen instructions the second time he just quickly blipped the accelerator also the engine was hotter so it passed.
There is no point taking the en gine to max revs if it goes bang and if the power drops off at high revs then why not lower the maximum to preserve the engine.
I was hoping to lower the max revs so it doesn't cause a
problem next year.
If the corsa and panda engines are made by Fiat how come they have GM cast into the block.

floatinglandrover said:

If the corsa and panda engines are made by Fiat how come they have GM cast into the block.

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When Fiat and GM first had their tie-in, Fiat could not keep up with demand for the little diesel. It is likely that GM are building it under licence, so their casting has their logo in it. When the Corsa first got this engine, many Vauxhall dealers were subcontracting warranty diagnosis to the Fiat dealers.

This engine is also used in the Peugeot Bipper and Citroen Nemo vans as its the same as the Fiorino.

Possibly diesel engines do not have rev limiters like petrol engines as combustion can't keep up at high revs.

a diesel engine should never be revved with no load on it
they arent designed for it so if your mot man put his foot to the floor then basically you do not want to go there again

My last MOT on my MJ was done while I waited, and I did hear the nuts being revved off a car, and then I realised it was mine !
It seems that the smoke test for a diesel is done by flooring the throttle while a smoke probe is stuck up the exhaust.
If it doesn't pass then it can be repeated up to a total of 6 times.
Old type diesels (before electronic control) had a mechanical system (a governor) that cut off the fuel over a certain revs. This is now achieved by the electronic control system.
So there is no governor in an MJ, just a bit of software.
I'd love to know if there is a way of reducing the maximum revs setting in the software as I don't like the idea of someone flooring the throttle on my well driven (normally) little car.
Also makes me wonder if the few MJs that have suffered cam chain failures had been recently MOT'd.
This post has made me realise that best practice is to get a while you wait MOT and make sure the engine is warmed up nicely and given a mild thrash beforehand so hopefully only one smoke test revving is required.

They must bounce it off the limiter for the smoke test. It's in the MOT rule book, same deal with our version of the MOT.