General High idle revs
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General High idle revs
Inlet side air leak ("vacuum leak") anywhere on the inlet side of the throttle body.
Sticking throttle butterfly or over tight or sticking throttle cable (should be plenty of slack)
Some eeedjut has been twiddling with the throttle stop screw on the throttle body.
Leaks will tend to hiss (listen for hiss with stethoscope or small diameter hose -- windscreen washer hose, etc.). You can check that the throttle butterfly closes if you remove the air filter gubbins.
Over fast idle is (almost) always too much air.
Sticking throttle butterfly or over tight or sticking throttle cable (should be plenty of slack)
Some eeedjut has been twiddling with the throttle stop screw on the throttle body.
Leaks will tend to hiss (listen for hiss with stethoscope or small diameter hose -- windscreen washer hose, etc.). You can check that the throttle butterfly closes if you remove the air filter gubbins.
Over fast idle is (almost) always too much air.
Cheers! Will have a look I also started to notice that when the car has been running a while and im sat in neutral, it revs then stop revs then stops. It's also started going through coolant quite quickly, any ideas?
Should use no coolant.
Quite often they develop very small leaks from the water pump, the water rail O ring, or the water rail itself (tube that runs along the front of the engine block). Generally the only way to spot these is to bring the car up to temperature and crawl under it with the engine running, look upwards. But if you can't see anything, compression test.
The pulsing idle can be an air leak, but sometimes just means that you need to clean the throttle body. Get hold of some cheap carb or brake cleaner (often poundshops or Netto/Liddle/Aldi will have some). Clean the outside, then remove the throttle body and clean the inside.
These are easy cars to work on, so don't be scared of DIY. The Haynes Cinquecento manual is useful (the engines are very similar, the chassis nearly identical, and the Haynes is easy to find your way around) and the Seicento Technicak Manuak is a 3 part download in the "Downloads" section here. You need a (free) program capable of opening .rar files. Google will find.
Quite often they develop very small leaks from the water pump, the water rail O ring, or the water rail itself (tube that runs along the front of the engine block). Generally the only way to spot these is to bring the car up to temperature and crawl under it with the engine running, look upwards. But if you can't see anything, compression test.
The pulsing idle can be an air leak, but sometimes just means that you need to clean the throttle body. Get hold of some cheap carb or brake cleaner (often poundshops or Netto/Liddle/Aldi will have some). Clean the outside, then remove the throttle body and clean the inside.
These are easy cars to work on, so don't be scared of DIY. The Haynes Cinquecento manual is useful (the engines are very similar, the chassis nearly identical, and the Haynes is easy to find your way around) and the Seicento Technicak Manuak is a 3 part download in the "Downloads" section here. You need a (free) program capable of opening .rar files. Google will find.
Just to add to the above, if the coolant is going down and there is no sign of an actual leak get it compression tested asap.
yep any garage should be able to do compression test - or just buy a compression tester - can pick them up for around £15.
Cleaned the throttle body today. Now got normal idle and much smoother running!
