Hi Guys! Hope anyone can help me with this one (he says with a doubtful look). My 2001 1.2 8v Punto has a very peculiar running order. It won't rev past 2500 rpm! It's almost like it reaches a limiter at 2500 and sends the revs back down to tickover again. If you keep your foot down it sounds like a bike on the limiter! Went for a MOT, and they obviously couldn't do the emmissions so he put it on his reader and it showed up Cat. Not a Fiat dealer mind. So he's put a new Cat on and guess what? It still does it!! Gonna be disappionted tomorrow when I tell him to put my original one back on and I'll go to a fiat dealer for proper diagnosis!

But does anyone have a clue??

Cheers guys!!

Have a look around all of your air intake, take off the air filter and then try it see if it does the same. If so take a look in the throttle body see if there is any visable dirt/blockage

If you have a laptop, you might benefit by arming yourself with a cheap VAG-COM KKL lead/adapter (mine was £8.20 inc. P&P from e-Bay) and the free software from FiatECUScan.net. With that you can see what error codes are cropping up, monitor various parameters dynamically and also test sensors and actuators like throttle position and injectors.

red.

could be a few things, go with the above suggestion and see what it pulls up. problem is, when some things go bad, the ecu doesn't always know about it so it can be hit and miss.

with this particular issue, my first port of call would be the crank sensor. although saying that, when was the fuel filter last changed?

It could also be an air leak into the inlet manifold muddling up the mixture settings. Or even the cam belt has slipped a few teeth.

Is it better or worse when the engine is cold(?) as that could hint at the O2 sensor.

nedge2k said:

could be a few things, go with the above suggestion and see what it pulls up. problem is, when some things go bad, the ecu doesn't always know about it so it can be hit and miss.

with this particular issue, my first port of call would be the crank sensor. although saying that, when was the fuel filter last changed?

Click to expand...

MK2 puntos tend to not need new air filter, they are built into the fuel pump, so it means replacing the entire pump!

bredsticz said:

MK2 puntos tend to not need new air filter, they are built into the fuel pump, so it means replacing the entire pump!

Click to expand...

Of course you meant "fuel filter". Don't want to confuse anyone.

red said:

Of course you meant "fuel filter". Don't want to confuse anyone.

Click to expand...

LMAO!! Yes i did! I'd be a bit worried if the air filter was in the fuel pump

My bad

As mentioned, take an inspection around air intake components, similar thing happened when a friend of mine put two performance filters in the bay of his corsa b. LOL.