FIAT Uno 45 - Manual (Page 50)

Engine idles roughly
Ⅵ Ⅵ
Mixture too weak
Ⅵ Ⅵ Air leak in carburettor
Ⅵ Ⅵ Air leak at inlet manifold to cylinder head, or inlet manifold to
carburettor
Ⅵ Ⅵ Carburettor incorrectly adjusted
Ⅵ Ⅵ Other fuel system fault (see Chapter 3)
Ⅵ Ⅵ Low tension leads on coil loose
Ⅵ Ⅵ Low tension lead to distributor loose
Ⅵ Ⅵ Dirty, incorrectly set, or pitted contact breaker points
Ⅵ Ⅵ Tracking across inside of distributor cover
Ⅵ Ⅵ Faulty coil
Ⅵ Ⅵ Ignition leads loose
Ⅵ Ⅵ Spark plugs fouled or incorrectly gapped.
Ⅵ Ⅵ Ignition timing incorrect
Ⅵ Ⅵ Other ignition fault (see Chapter 4)
Ⅵ Ⅵ Incorrect valve clearances
Ⅵ Ⅵ Widely differing cylinder compressions
Ⅵ Ⅵ Low battery voltage (charging fault)
Ⅵ Ⅵ Battery leads loose on terminals
Ⅵ Ⅵ Battery earth strap loose on body attachment point
Ⅵ Ⅵ Engine earth lead loose
Pre-ignition (pinking) during acceleration
Ⅵ Ⅵ Incorrect grade of fuel being used
Ⅵ Ⅵ Ignition timing over-advanced
Ⅵ Ⅵ Other ignition fault (see Chapter 4)
Ⅵ Ⅵ Engine overheated
Ⅵ Ⅵ Excessive carbon build-up
Ⅵ Ⅵ Fuel system fault (see Chapter 3)
Ⅵ Ⅵ Valve timing incorrect (after rebuild)
Ⅵ Ⅵ Mixture too weak
Engine runs on after switching off
Ⅵ Ⅵ Idle speed too high
Ⅵ Ⅵ Incorrect type of spark plug
Ⅵ Ⅵ Overheating
Ⅵ Ⅵ Excessive carbon build-up
Ⅵ Ⅵ Other emission control fault (see Chapter 3)
Oil being lost due to leaks
Ⅵ Ⅵ Leaking oil filter gasket
Ⅵ Ⅵ Leaking rocker cover gasket
Ⅵ Ⅵ Leaking timing gear cover gasket
Ⅵ Ⅵ Leaking sump gasket
Ⅵ Ⅵ Loose sump plug
Low oil pressure (verify accuracy of sender before
dismantling engine!)
Ⅵ Ⅵ Oil level low
Ⅵ Ⅵ Engine overheating
Ⅵ Ⅵ Incorrect grade of oil in use
Ⅵ Ⅵ Oil filter clogged or bypass valve stuck
Ⅵ Ⅵ Pressure relief valve stuck or defective
Ⅵ Ⅵ Oil pick-up strainer clogged or loose
Ⅵ Ⅵ Main or big-end bearings worn
Ⅵ Ⅵ Oil pump worn or mountings loose
Excessive oil consumption
Ⅵ Ⅵ Overfilling
Ⅵ Ⅵ Leaking gaskets or drain plug washer
Ⅵ Ⅵ Valve stem oil seals worn, damaged or missing after rebuild
Ⅵ Ⅵ Valve stems and/or guides worn
Ⅵ Ⅵ Piston rings and/or bores worn
Ⅵ Ⅵ Piston oil return holes clogged
Oil contaminated with water
Ⅵ Ⅵ Excessive cold running
Ⅵ Ⅵ Leaking head gasket
Ⅵ Ⅵ Cracked block or head
Oil contaminated with fuel
Ⅵ Ⅵ Excessive use of choke
Ⅵ Ⅵ Worn piston rings and/or bores
Unusual mechanical noises
Ⅵ Ⅵ Unintentional mechanical contact (eg fan blade)
Ⅵ Ⅵ Worn drivebelt
Ⅵ Ⅵ Worn valvegear (tapping noises from top of engine) or incorrect
clearance
Ⅵ Ⅵ Peripheral component fault (generator, coolant pump)
Ⅵ Ⅵ Worn big-end bearings (regular heavy knocking, perhaps less under
load)
Ⅵ Ⅵ Worn main bearings (rumbling and knocking, perhaps worsening
under load)
Ⅵ Ⅵ Small-end bushes or gudgeon pins worn (light metallic tapping)
Ⅵ Ⅵ Piston slap (most noticeable when engine cold)
Ⅵ Ⅵ Worn timing chain and gears (rattling from front of engine)
Ⅵ Ⅵ Worn crankshaft (knocking, rumbling and vibration)
1•36 All engines