I have a 96 P reg Punto 55 which looses it's power when accelerating hard, I have replaced both ign coils & checked spark plugs & ign leads. The car has a slightly rough tickover, it starts Ok & doesn't cut out. When the engine is revved from standstill it will not achieve maximum rpm, but surges. I have scanned it with a Snap-on scanner but no error codes are present. Can anyone help please?

lambda sensor maybe

Have a look at

http://www.parttrackers.com/library/1/24/36/

If you can convert American terminology to English, and accept you don't have OBD (but no error codes anyway), the practicality of the thing is exactly what you're looking for

If you have the snap-on mt2500 you will be able to monitor live-data; So have a drive and watch lambda-data and mapsensor data.
Geert

How much does the snap-on meter cost?

Pete.
Cinq sporting 1242cc
Cinqs&Seis Yahoo group
Clubcento

I bought mine last year for 1600 euro and it came with 3 cartridges which you could choose. Since then I bought the fiat-alfa-lancia cartridge and teh EOBD cartridge these cost about 500 euro each.
Geert

ah.

Might not bother then.

Cheers anyway!!

Pete.
Cinq sporting 1242cc
Cinqs&Seis Yahoo group
Clubcento