Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Cooling System
The coolant pump shell is integrated in the timing cover. The pump wheel is still driven by the auxiliary unit's transmission.
The coolant pump pumps coolant through the cylinder block, and also cools the cylinder head, cylinder sleeves, spark plug wells, intake ducts and fuel injection nozzles.
The coolant flows in at the coolant pump and passes through a number of channels before it collects and then flows out to the thermostat housing. If the thermostat housing is closed, the coolant passes via the by-pass channel directly to the coolant pump to then circulate through the cylinder block again.
For the turbocharged engine, the task of the cooling system is to supply the turbocharger with coolant.
Coolant pump and drive gear
Alternator/clutch
The belt pulleys on alternator and intermediate shaft have improved surface treatment.
On the alternator shaft between alternator and intermediate shaft there is a clutch with a freewheel (one-way clutch) at each end. The function is to filter the engine's different irregular shape and thus avoid gear rattle/noise in the geartrain.
In connection with introduction of EHPAS (electric servo pump), the belt-driven servo pump with its heavy steel belt pulley is discontinued as well as the clutch for the coolant pump. The reduced rotating moment of inertia means more freewheeling, primarily when idling.
To reduce/avoid wear, the drive gears' outer ring (against the one-way clutch's friction band), are treated with nitride.
AC bracket
The AC compressor's fastening bracket is simplified. Earlier solution with a main bracket and three separate stays, is replaced by a modified bracket which has the front reinforcement stay integrated and a new fastening point in the transmission. The change means, except that the fastener assembly has 9 fewer bolts, that the installation method becomes easier and there is no longer a need for any special tools when assembling.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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