Bearing damage (VW Golf 3)

A knocking noise from the engine compartment, which becomes louder when the oil is warmer, is an indication of bearing damage. Almost always, this is a defect in the connecting rod plain bearings; damage to the crankshaft main bearings is very rare.

Reasons

Too high a number of revolutions when the engine is cold and hence - viscous oil.

Water in engine oil as a result of a defective cylinder head gasket.

Insufficient lubrication due to too low oil level.

Lubricating film with breaks at high oil temperatures, possibly due to incorrect oil selection.

Note: A knocking, rpm-dependent, crackling noise of considerable volume may not indicate engine damage. It may be due to harmless injector needles: the spring-compressed injector needles, which usually rise under fuel pressure and thus open the injector opening, remain "suspended".

In this case, the engine no longer receives properly injected fuel and therefore draws attention to itself with a noticeable noise.

This rather harmless defect can appear when, during work on the injection system carried out without observing cleanliness, dirt gets into the fuel lines and a piece of dirt pinches the injector needle. Anyone who takes this into account can help themselves if, with the

[The original text can be found at: www.vwmanual.ru]

clutch briefly and strongly press the gas. The fuel flow will wash the needle and it. possibly, will be released again. If the foreign body does not come out in this way, then you need to clean the injectors. In this case, we are talking about you sequentially loosening the nuts of the injectors one after another and tightening them again where the noise decreases when loosened, and the "troublemaker" sits.