1999 FIAT PUNTO fuel pressure

Diesel engine in-car repair procedures
2C*11

10 firmly apply the handbrake, then jack up
Ihe
front of the car and support it securely on
arte stands
(see Jacking and vehicle support). Remove the right-hand front roadwheel. 11 Working under the wheelarch. remove the splash guard, than unbolt and remove the outer cover over the crankshaft pulley (see ilustratlon). 12 Remove the auxiliary drivebelt(s) as described in Chapter 18. 13 Unbolt and remove the lower timing cover from the cylinder block (see Illustration). Note that one of the bolts is located at the
Iron!
of the engine. 14 Unscrew the four socket-headed bolts
and
remove the pulley from the front of the crankshaft (see illustrations). Recover the {pacer plate. 15 Turn the engine in its normal direction of rotation (using a socket or spanner on the crankshaft sprocket centre bolt) until pressure
can be
felt at No 1 cylinder gtowplug hole. 16 Continue turning the engine until the TDC timing marks on the camshaft and fuel injection pump sprockets are aligned with the corresponding marks on the timing belt inner cover, and the crankshaft sprocket timing
mark
is aligned with the mark on the oil pump cover (see illustration). 17 Tne engine is now set at TDC tor No 1 e>llnder on compression.
114a Unscrew and remove the socket-headed bolts and spacer...
2.11 Removing the outer cover over the 2.13 Removing the lower timing cover crankshaft pulley
2.14b ... and remove the pulley from the 2.18 Sprocket timing mark positioning with No 1 cylinder et TDC front of the crankshaft

2C*2 Diesel engine in-car repair procedures
4.4a Unbolt the engine oil dipstick tube...
3 Cylinder compression test
Note: A compression tester specifically designed for diesef engines must be used for this test. 1 When engine performance Is down, or if misfiring occurs, a compression test can provide diagnostic clues as to the engine's condition, If the lest is performed regularly, it can give warning of trouble before any other symptoms become apparent. 2 A compression tester specifically Intended for diesel engines must be used, because of the higher pressures involved. The Ie6ter is connected to an adapler which screws Into the glow plug or injector hole. It is unlikely to be worthwhile buying such a tester for occasional use. but it may be possible to borrow or hire one • if not. have the test performed by a garage. 3 Unless specific instructions to the contrary are supplied with the tester, observe the following points: 9) The battery must bo in a good state of charge, the air titter must be clean, end the engine should be at normal operating temperature. b) AH the in/actors or glow plugs should be removed before starting the lest. If removing the injectors, also remove the flame shield washers, otherwise they may be blown out. c) The stop solenoid must be disconnected.
4.4b ... and remove it from the rubber grommet in the oil pump housing
fo prevent the engine from running or fuel from being discharged. 4 There is no need to hold the accelerator pedal down during the test, because the diesel engine air inlet is not throttled. 5 The cause of poor compression Is less easy to establish on a diesel engine than on a petrol one. The effect of introducing oil into the cylinders (wet testing) Is not conclusive, because there is a risk that the oil will sit in the recess on the piston crown, instead of passing to the rings. However the following can be used as a rough guide to diagnosis. 6 All cylinders should produce very similar pressures; a difference of more than 5 bars between any two cylinders Indicates the existence of a fault. Note that the compression should build up quickly In a healthy engine; low compression on the first stroke, followed by gradually-increasing pressure on successive strokes, indicates worn piston rings. A low compression reading on the first stroke, which does not build up during successive strokes, indicates leaking valves or a blown head gasket (a cracked hoad could also be the cause). 7 A low reading from two adjacent cylinders Is almost certainly due to the head gasket having blown between them: the presence of coolant In the engine oil will confirm this,
Leakdown test 8 A leakdown test measures the rate at which compressed air fed into the cylinder Is lost. It is an alternative to a compression test, and in many ways it is better, since the escaping air provides easy identification of where pressure loss is occurring (piston rings, valves or head gasket). 9 The equipment needed for leakdown testing is unlikely to be available to the home mechanic. If poor compression Is suspected, have the test performed by a suitably-equipped garage.
4 Timing belt and covers -removal
and
refitting
Note: Fiat specify the use of a spec/a/ timing belt tension measuring tool to correctly set the timing belt tension. If access to this equipment cannot be obtained, an approximate setting can be achieved using the method described below. If the method described is used, the tension must be checked using the special tool at the earliest possible opportunity. Do not drive the vehicle over large distances, or use high engine speeds, until the belt fens/on rs known to be correct. Refer to a Fiat dealer for advice.
General Information 1 The function of the timing belt is to drive the camshaft and fuel injection pump. Should the belt slip or break in service, the valve timing will be disturbed and piston-to-valve contact
will occur, resulting In serious engine damage. 2 The timing bolt should be renewed at the specified intervals (see Chapter 1B), or earlier If It is contaminated with oil. or If It is at al noisy In operation (a scraping noise due to uneven wear),
Removal 3 Set the engine at TDC on No 1 cylinder
as
described in Section 2. 4 Unbolt and remove tho engine oil dipstick tube and remove It from the rubber gromme! in the oil pump housing (see illustrations), 5 Before removing the timing belt check rts tension by turning the belt through 90" with finger and thumb midway between u* injection pump and camshaft sprockets. This will give you an Idea of the tension to apply when refitting, assuming the tension is already correct. Also note the position of the tensions pulley as a reference mark. 6 Release tho nut on the timing bea tensioner, move the tensioner pulley away from the belt and retlghten the nut to hold the pulley in the retracted position. 7 If the timing belt is to be re-used, use white paint or chalk to mark the direction of rotation on the belt (if markings do not already exist), then slip the belt off the camshaft, crankshaft and injection pump sprockets, and the idler and tensioner pulleys. Caution: If the belt appears to be In good condition and can be re-used, it fs essential that It Is refitted the same
wsy
round, otherwise accelerated wear will result, leading fo premature failure. 8 Check the timing belt carefully for any signs of uneven wear, splitting, or oil contamination. Pay particular attention to the roots of the teeth. Renew it if there is the slightest doutt about its condition. If the engine is undergoing an overhaul, renew the belt as a matter of course, regardless of its apparent conditio*. The cost of a new belt Is nothing compa/ed with the cost of repairs, should the belt freak in service. If signs of oil contamination art found, trace the source of the oil leak and rectify It. Wash down the engine timing baft area and all related components, to remove
sd
traces of oil.
Refitting 9 Before refitting, thoroughly clean the tknmg belt sprockets. Check that the tensioner and idler pulleys rotate freely, without any sign ol roughness. If necessary, renew them as described in Section 5. 10 Ensure that the crankshaft, camshaft and injection pump sprockets are still at their TDC positions as described In Section 2. 11 Engage the timing belt with the crankshaft sprocket, then locate it around the idler pufiey and onto the Injection pump sprocket making sure that it is kept taught. Continue to locate! around the camshaft sprocket and finally around Ihe tensioner pulley (see Illustration) Ensure the belt teeth seat correctly on Ihe sprockets.

2D*10 Engine removal and overhaul procedures
1 General information
Included In (his Part of Chapter 2 are details of removing the engine/transmission from the car and general overhaul procedures for tho cylinder head, cylinder block/crankca9e and all other engine internal components. The information given ranges from advice concerning preparation for an overhaul and the purchase of replacement parts, to detailed step-by-step procedures covering removal, inspection, renovation and refitting of engine Internal components. After Section 5, all instructions are based on the assumption that the engine has been removed from the car. For Information concerning in-car engine repair, as well as the removal and refitting of those external components necessary for full overhaul, refer to Part A, 8 or C of this Chapter (as applicable) and to Section 5. Ignore any preliminary dismantling operations described in Part A. B or C that are no longer relevant onca the engine has been removed from ihe car.
2 Engine overhaul -general information
1 It Is not always easy to determine when, or if, an engine should be completely overhauled, as a number of lectors must be considered. 2 High mileage Is not necessarily an Indication that an overhaul Is needed, while low mileage does not preclude the need for an overhaul. Frequency of servicing Is probably the most important consideration. An engine which has had regular and frequent oil and filter changes, as well as other required maintenance, should give many thousands of miles of reliable service. Conversely, a neglected engine may require an overhaul very early In its life. 3 Excessive oil consumption Is an Indication that piston rings, vaivo seals and/or valve guides are in need of attention. Make sure that oil leaks are not responsible before deciding that the rings and/or guides are worn Perform a compression test, as described In Parts A or B (petrol engines) or C (diesel engines) of this Chapter, to determine the likely cause of the problem. 4 Check the oil pressure with a gauge fitted In place of the oil pressure switch. If it Is extremely low. the main and big-end bearings, and/or the oil pump, are probably worn out. 5 Loss of power, rough running, knocking or metallic engine noises, excessive valve gear noise, and high fuel consumption may also point to Ihe need for an overhaul, especially if
they are all present at the same time. If a complete service does not remedy the situation, major mechanical work is the only solution. 6 An engine overhaul involves restoring ell Internal parts to the specification of a new engine. During an overhaul, the cylinders are rebored (where applicable), the pistons and the piston rings are renewed. New main and big-end bearings are generally fitted; If necessary, the crankshaft may be reground. to restore the journals. 7 The valves are also servrced as well, since they are usually In less-than-perfect condition at this point. While the engine is being overhauled, other components, such as the starter and alternator, can be overhauled as well. The end result should be an as-new engine that will give many trouble-free miles. Note: Critical cooling system components such as the hoses, thermostat and coolant pump should be renewed when an engine is overhauled. The radiator should be checked carefully, to ensure that it is not clogged or leaking. A/so. it Is a good Idea to renew the ofI pump whenever the engine i$ overhauled.
8 Before beginning the engine overhaul, read through tho entire procedure, to familiarise yourself with the scope and requirements of the job. Overhauling an engine is not difficult If you follow carefully all of the instructions, have the necessary tools and equipment, and pay close attention to all specifications. It can, however, be time-consuming. Plan on the car being off the road for a minimum of two weeks, especially If pans must be taken to an engineering wo'kd for repair or reconditioning.
9 Check on the availability of parts and make sure that any necessary special tools and equipment are obtained in advance. Most work can be done with typical hand lools, although a number of precision measuring tools are required (or Inspecting parts to determine if they must be renewed. Often the engineering works will handle the inspection of parts and offer advice concerning reconditioning and renewal, Note: Always wait unt'l the engine has been completely dismantled, and until all components (especially the cylinder block/crankcase and the crankshaft) have been inspected, before deciding what service and repair operations must be performed by an engineering works. The condition of these components will be the major factor to consider when determining whether to overhaul the original engine, or to buy a reconditioned unit. Do not. fh ere tore, purchase parts or have overhaul work done on other components until they have been thoroughly Inspected. As a general rule, time is the primary cost of an overhaul, so it does not pay to fit worn or sub-standard parts.
10 As a final note, to ensure maximum life and minimum trouble from a reconditioned engine, everything must be assembled wilh care, in a spotlessly-clean environment.
3 Engine and transmission removal -methods
and
precautions
1 If you have decided that the engine must be removed for overhaul or major repair work, several preliminary steps should be taken. 2 Locating a suitable place to work is extremely important. Adequate work space, along with storage space for the car, will be needed. If a workshop or garage Is not available, at the very least, a flat, level, clean work surface Is required. 3 Cleaning the engine compartment and engine/transmission before beginning the removal procedure wilt help keep tools clean and organised. 4 An engine hoist or A-frame will also be necessary. Make sure the equipment is rated In excess of the combined weight of the engine and transmission, Safety Ib of primary Importance, considering the potential hazards involved in lifting the engine/transmission out of the car. 5 If this is Ihe first time you have removed
an
engine, an assistant Bhould Ideally be available. Advice and aid from someone more experienced would also be helpful. There are many instances when one person cannot simultaneously perform all of the operations required when lifting the engine out of Ihe vehicle. 6 Plan the operation ahead of time. Before starting work, arrange for the hire of or obtain all of the tools and equipment you will need. Some of the equipment necessary to perform engine/transmission removal and Installation safely and wilh relative ease On addition to an engine hoist) Is as follows: a heavy duly trolley jack, complete sets of spanners and sockets as described in the reference section of this manual, wooden blocks, and plenty of rags and cleaning solvent for mopping up spitted oil, coolant and fuel. If the hoist must be hired, make sure that you arrange for it In advance, and perform all of the operations possible without it beforehand. This will save you money and time.
7 Plan for the car to be out of use for quite a while. An engineering works will be required to perform some of the work which the do-it-yourselfer cannot accomplish without special equipment. These places often have a busy schedule, so it would be a good idea to consul! them before removing the engine, in order to accurately estimate the amount of time required to rebuild or repair components that may need work, 9 Always be extremely careful when removing and refitting the engine/transmission. Serious injury can result from careless actions. Plan ahead and take your time, and a job of this nature, although major, can be accomplished successfully.

2D*10 Engine removal and overhaul procedures
12.18 Angle-tightening the main bearing cap bolts (petrol engine)
12.Ida Application area for silicone Instant gasket on crankshaft rear oil seal housing (petrol engine) 12.19b Refitting the crankshaft rear oil seal housing (petrol engine)
19 Fit a new oil seal to the crankshaft rear oil seal housing. Apply grease to the seal lips. On 1108 cc petrol engines a conventional gasket Is not used at the oil seal retainer joint face, but a 3 mm diameter bead of RTV (Instant) silicone gasket must be applied as shown -allow at least one hour 1or the gasket to cure before oil contacts it. On all other engines a gasket Is fitted Securely tighten the housing bolts (see Illustrations). 20 Check that Ihe crankshaft rotates freely by turning It by hand. If resistance Is fell, re-check the running clearances, as described above. 21 Carry out a check of the crankshaft endfloat as described at the beginning of Section 8. If the thrust surfaces of the crankshaft have been checked and new thrust washers hove been fitted, then the endfioat should be within specification.
22 Refit the pistons and connecting rods as described in Section 7. 23 Refit the flywheeVdriveplate, and-vibration plate (16-valvo engines), oil pump and pick-up tube, and sump with reference to the relevant Sections of Parts A, B or C of this Chapter.
13 Engine -initial start-up after overhaul and reassembly
1 With the engine refitted In the vehicle, double-check the engine oil and coolant levels. Make a final check that everything has been reconnected, and that there are no tools or rags left In the engine compartment.
Petrol engine models 2 Remove the spark plugs, then disable the
ignition system by disconnecting the LT wiring plug to the ignition colls. 3 Turn the engine on the starter until Ihe oi pressure warning light goes out. Refit ihe spark plugs, and reconnect the LT wiring.
Diesel engine models 4 Disconnect tho wiring from the stop solenoid on the Injection pump, then turn the engine on the starter motor until the oil pressure warning light goes out. Reconnect ihe wire to the stop solenoid. 6 Fully depress the accelerator pedal, turn tho ignition key to its first position and wait tor HHJ preheating warning light to go out.
All models 6 Start the engine, noting that this may take i little longer than usual, due to the fuel system components having been disturbed.
12.19c On diesel engines use a screwdriver to prise out the rear oil seal 12.19d Locate the new oil soalln the housing (diosel engine)... 12.19e ... and use a block of wood to drive it in
12.19f On Diesel engines fit the gasket to the cylinder block ... 12.19g ... then locate the rear oli seal housing... 12.19h ... and Insert the bolts

4A«1
Chapter 4 Part A:
Fuel system - single-point petrol injection models
Contents
Accelerator cable • removal, refitting and adjustment 4 Air cleaner and inlet system - removal and refitting 2 Air cleaner filter element renewal See Chapter 1A Engine management system components - removal 8nd refitting .. 5 fuel filter renewal See Chapter 1A Fuel injection system - depressurlsatlon 8 Fuel injection system • testing and adjusting 10
Degrees of difficulty
Fuel pump/fuel gauge sender unit - removal and refitting 8 Fuel tank - removal and refitting 7 General information and precautions 1 Idle speed and mixture adjustment See Chapter 1A Inlet air temperature regulator • removal and refitting 3 Inlet manifold - removal and refitting 9 Unleaded petrol - general Information and usage 11
Easy, suitable for Fairty easy, suitable Fairly difficult, Jx suitable for competent ^ OY mechanic ^
DifficUt, suitable tor % Very difficult, ^ novice with Me for begrmer with &
Fairly difficult, Jx suitable for competent ^ OY mechanic ^ experienced DIY > * suitable for expert D(Y JS or professional ^ experience some experience &
Fairly difficult, Jx suitable for competent ^ OY mechanic ^ mechanic > * suitable for expert D(Y JS or professional ^
Specifications
System type Weber-Marelll integrated single-point fuel injection/ignition system
Fuel system data Fuel pump type Electric, Immersed in fuel tank Fuel pump delivery rate 110 litres/hour minimum Regulated fuel pressure 1.0 ± 0.2 bar Crankshaft TDC sensor resistance at 20°C €50 to 720 ohms Injector duration (at idle)
1
£ ms
Recommended fuel Minimum octane rating 95 RON unleaded
Torque wrench settings Nm ibfft Coolant temperature sensor 3 2 Fuel filter collar nut S 4 Fuel tank 28 21 Idle control stepper motor 4 3 Inlet manifold 27 20 Inlet union to filter 31 23 Outlet union to filter 15 11 Throttle body to manifold 7 5 Throttle potentiometer 3 2