Note t Metal glow plugs are always fitted in the 2.7 ltr. common rail engine.

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1 Removing and insalling glow plugs Page 1 of 5 Removing and insalling glow plugs Noe Meal glow plugs are always fied in he 2.7 lr. common rail engine. Two differen ypes of glow plugs are fied in he 3.0 lr. common rail engine (engine code leers BMK and BNG): Bosch ceramic glow plugs or Beru meal glow plugs. I is very imporan o use he correc ype of glow plugs depending on he sofware version of he engine conrol uni, oherwise he glow plugs will be irreparably damaged when he igniion is swiched on. The following safey precauions are only required on 3.0 lr. common rail engines wih engine code leers BMK and BNG up o and including model year Cauion Mixed insallaion of ceramic glow plugs and meal glow plugs on he same engine is no permissible. The sofware of he engine conrol uni is specifically adaped o eiher he ceramic or he meal glow plugs, so i is imporan o insall he correc ype. The glow plugs mus no be removed when checking cylinder compression. The compression es is performed via he Guided Faul Finding funcion. Transpor and sore only in original packaging or packed separaely in bubble wrap. Do no remove from packaging unil immediaely prior o insallaion. Afer removal, he cylinder head mus no be pu down on he gaske side wih he glow plugs sill insalled, because he glow plugs projec beyond he gaske surface. Idenifying he differen ypes of glow plugs for he 3.0 lr. common rail engine: A - Ceramic glow plugs are colourcoded wih a whie seal -arrowand have a chamfered shoulder a he ip. B - Meal glow plugs are colour-coded wih a red seal -arrow-. Removing ceramic glow plugs (Bosch) Cauion Due o he special properies of he maerial used, he ceramic glow plugs (Bosch ype GSK3) are easily damaged and require exra care when handling and insalling. Always insall a new ceramic glow plug if you are no sure he old one is in perfec condiion. If a ceramic glow plug has been damaged or he heaer pin is broken, his will invariably cause engine damage.

2 Removing and insalling glow plugs Page 2 of 5 If he heaer pin of he glow plug is broken, he fragmens mus be removed from he engine before saring for he firs ime, oherwise his will cause mechanical damage (pison seizure). Remove he relevan cylinder head if necessary. Before removal, he ceramic glow plugs mus be burn clean using he final conrol diagnosis funcion in he diagnosic eser. Noe Wai for 60 seconds each ime afer performing final conrol diagnosis of glow period conrol uni. The igniion mus remain swiched on. If you do no wai for 60 seconds (if igniion is swiched off and immediaely swiched on again), he glow plugs can be damaged (due o repeaed pre-heaing). The acivaion of he glow plugs is conrolled according o coolan emperaure. Clean glow plug openings in cylinder head; make sure no dir ges ino cylinder. Noe Cleaning procedure: Use a vacuum cleaner o remove coarse dir. Spray brake cleaner or suiable cleaning agen ino glow plug openings, le i work in briefly, and blow ou wih compressed air. Then clean he glow plug openings using a cloh moisened wih oil. When loosening and ighening ceramic glow plugs, use special ool U/J exension and socke, 10 mm and a suiable orque wrench. Unplug he connecor from he glow plug o be removed. When loosening a ceramic glow plug, do no exceed he maximum release orque of 20 Nm. When loosening, always use U/J exension

3 Removing and insalling glow plugs Page 3 of 5 and socke, 10 mm and a orque wrench. Noe If he ceramic glow plugs are difficul o remove (release orque more han 20 Nm), use a suiable peneraing oil spray and ry again. If one of he ceramic glow plugs canno be loosened by applying he maximum release orque of 20 Nm, he cylinder head mus firs be removed Rep. gr.15 so he glow plug can be unscrewed. Then unscrew ceramic glow plug carefully by hand or using a suiable hose. Keep he glow plug sraigh while unscrewing. Carefully pull ceramic glow plugs ou from above using a suiable ool (such as a lengh of hose). Take care o preven glow plugs from conacing oher pars. Insalling ceramic glow plugs Cauion IMPORTANT: always observe he precauions lised above. The hreads in he cylinder head and on he ceramic glow plugs mus be dry, and free of oil and grease. Noe Before insalling glow plugs, clean combusion deposis ou of glow plug openings in cylinder head. Screw in ceramic glow plugs fingerigh. I is imporan o keep o he specified ighening orque for glow plugs: 12 Nm (hreads dry and free of oil and grease). The heaer pins of he glow plugs can break if his orque seing is no observed, which invariably causes engine damage. Check funcion of ceramic glow plugs afer insallaion and before saring engine for he firs ime.

4 Removing and insalling glow plugs Page 4 of 5 Afer insallaion, check elecrical resisance direcly a glow plug conacs: no greaer han 1 Ohm If his specificaion is no obained (resisance greaer han 1 Ohm), remove defecive ceramic glow plug again and check wheher heaer pin is broken. If a broken heaer pin is visible, i is very imporan o remove he fragmens from he engine before saring for he firs ime. Deach cylinder head if necessary; oherwise his will resul in mechanical damage o he engine. Reconnec elecrical connecors on ceramic glow plugs. Make sure ha connecor engages properly. Addiionally check ceramic glow plugs via self-diagnosis. Erase even memory of engine conrol uni. Do no sar engine a his sage. Perform final conrol diagnosis (auomaic glow period conrol uni - J179-). Inerrogae even memory again. Do no sar engine a his sage. The engine mus no be sared if he even memory has regisered a faul relaing o he ceramic glow plugs. Check ha elecrical connecors have engaged properly. Removing meal glow plugs: Special ools and workshop equipmen required Torque wrench -V.A.G U/J exension and socke, 10 mm Cauion Mixed insallaion of ceramic glow plugs and meal glow plugs on he same engine is no permissible. Swich off igniion. Deach glow plug connecors from glow plugs which are o be removed.

5 Removing and insalling glow plugs Page 5 of 5 Clean glow plug openings in cylinder head; make sure no dir ges ino cylinder. Noe Cleaning procedure: Use a vacuum cleaner o remove coarse dir. Spray brake cleaner or suiable cleaning agen ino glow plug aperures, le i work in briefly, and blow ou wih compressed air. Then clean he glow plug openings using a cloh moisened wih oil. To slacken he glow plugs use special ool U/J exension and socke, 10 mm Then unscrew glow plugs carefully by hand or using a suiable hose. Keep he glow plugs sraigh while unscrewing. Insalling meal glow plugs Before insalling glow plugs, clean ou combusion deposis from glow plug bores in cylinder head. To ighen he glow plugs use special ool U/J exension and socke, 10 mm wih a suiable orque wrench. Then ighen glow plugs o specified orque. l Tighening orque: 17 Nm Cauion If he ceramic glow plugs (Bosch) have been replaced wih meal glow plugs (Beru) he sofware of he engine conrol uni mus be flashed accordingly before connecing he glow plug connecors. If his is no done, he meal glow plugs will be IRREPARABLY DAMAGED WHEN THE IGNITION IS SWITCHED ON. Aach glow plug connecors correcly and make sure hey are securely fied.