Glow plugs have a long lifespan, however they do gradually deteriorate due to wear and tear. So how do you know if a set of glow plugs needs replacing?
Bougie de préchauffage pour Isuzu 8-97043744-0 8-94387612-1 8-97044037-0 Pi-59 84mm 11v
Dans cet article, nous examinons six signes courants qui indiquent que les bougies de préchauffage pourraient être défectueuses ou endommagées.
Something's wrong: the engine warning light
The engine warning light on the dashboard is often the first clue that something is wrong. Vehicles displaying this light should be taken to an authorised workshop for proper diagnosis and service as soon as possible. A number of faults can cause the engine warning light to illuminate – below, we outline the clues which point to faulty glow plugs.
Démarrage difficile
A hard starting engine is the most common indicator of damaged glow plugs. In cold conditions, without correctly functioning glow plugs, the combustion chamber may not reach the right temperature to ignite the fuel and start the engine. If there are no problems with the fuel or the battery, then glow plugs should be checked.
ratés du moteur
Le processus de combustion dans les moteurs diesel nécessite un taux de compression élevé, du carburant injecté au bon moment et dans la bonne quantité. Cela enflamme le carburant diesel, entraînant une combustion. Les ratés peuvent être causés par des problèmes de qualité du carburant, de compression et d'injection de carburant.
Ralenti brutal
If one or more glow plugs have burned out, are carbon fouled or damaged, the engine will become progressively harder to start as temperatures drop and will idle roughly and produce white smoke from the exhaust for several minutes once it finally starts. If all the glow plugs are burned at their tips, check the fuel injection timing.
Diminution de l'efficacité énergétique
Temperature and fuel usually determine fuel efficiency, not glow plug performance. However, in some cases, glow plugs do have a role to play.
Based on local climate, diesel may be blended with specific additives during the cold months to lower its freezing point. The blended fuel will most likely have a lower energy content and provide reduced fuel efficiency. Engine operating temperatures should be adjusted to ensure all the injected fuel is completely burnt. Glow plugs help to provide the additional heat in the combustion chamber.
Bougie de préchauffage pour Isuzuv 5-81410044-0 Pi-53 95mm 20.5v
If the required temperature is not reached due to faulty glow plugs, the engine's performance will be weakened, and it will have to work extra hard to meet the demands of the road. The vehicle's fuel efficiency will be negatively affected.
Si la voiture présente d'autres symptômes répertoriés ici et commence également à afficher une efficacité énergétique réduite, elle doit être emmenée dans un atelier agréé pour un diagnostic et un entretien appropriés dès que possible.
fumée blanche
White smoke usually occurs when there is not enough heat to burn the fuel. The unburnt fuel particles travel out of the tailpipe as smoke and typically produce a rich fuel smell. It's not unusual to see white smoke from the exhaust during cold weather, until the engine has warmed up.
Bougie de préchauffage pour Isuzuv 8-94439218-0 Pi-55 89mm 5v
Des bougies de préchauffage endommagées ou un module de commande de bougie de préchauffage défectueux peuvent provoquer une fumée blanche au démarrage du moteur. Il existe également de nombreuses autres causes possibles d'un excès de fumée blanche, notamment une faible vitesse de démarrage du moteur, une faible compression et de l'air dans le système d'alimentation. Si de la fumée blanche est toujours visible après que le moteur s'est réchauffé, le moteur peut avoir un ou plusieurs injecteurs défectueux, un calage d'injection retardé ou une pompe d'injection usée.
Fumée noire
Black smoke is caused by an imbalance in the air-fuel ratio – too much fuel and not enough air. This means either too much fuel is being added to the mix or there is not enough oxygen being supplied to burn the fuel. Faulty glow plugs may disturb the sensitive diesel combustion process, which in turn might result in the engine producing black smoke from the tailpipe. This is a warning sign that something is wrong either with the glow plugs or other vital components of the combustion process.
