Oil has leaked into my Isuzu I-370's spark plugs, causing engine misfiring. What is the cause of this and how do I fix this in my garage?
The oil in your spark plug probably comes from a leaking valve gasket. You could tighten the valve seals to stop the leaking. However, more often not in this case, the valve needs to be replaced. If you do not have the time to take your I-370 to the technician, then you could DIY in the comfort of your garage given you have the know-how and experience. You would need a valve cover gasket kit, a vulcanizing sealant, a brake cleaner, a socket set, a putty knife, and a rubber mallet. First, determine the location of the valve gasket by looking at the owner's manual. Tap the cover loose by using a soft-faced mallet then remove the hoses, labels, and electrical connectors and attach to the valve cover. Clean any excess oil in the spark plug tubes using a rag wrapped around a screwdriver. Once the tubes are clean and the hoses disconnected, you are now ready to replace the valve gasket. Clean the valve cover first with the brake cleaner and place in the new one.
How do I fix my Isuzu I-370's clunking noise that seems to come out from its suspension?
To address this problem, you can either wait until it gets worse and easier to find or spraying the front end of the suspension with water to better observe where the noise is coming from. Usually, this is caused by bad sway bar bushings, faulty upper struts mounts, collapsed motor mounts, bad rack bushings, or loose brake backing plates. The struts are the springs that absorb the force created by the vehicle's moving motion. Thus, if the struts are faulty or misaligned, then it can definitely create strange noises. Also, the noise may be coming from the tires, which are part of the suspension system. They may be unevenly worn out thus it becomes more difficult to keep the vehicle on the ground therefore producing the clunking noise.
I noticed unusually thick white or grayish smoke coming out of my Isuzu I-370's exhaust pipe. Is this normal?
Thin white or grayish smoke is nothing to be worried about. This is just the product of condensation buildup in the exhaust system. However, if the smoke is thicker than usual, it could be a coolant or transmission problem. The engine may be burning more coolant than usual as a result of more complex problems such as a blown head gasket, a faulty cylinder head, or a chipped engine block. It may also be caused by a bad transmission modulator which causes the engine to suck and vaporize transmission fluid more than usual. Check the exhaust pipe whether it is wet and has a strong, sweet aroma to it. This may mean that coolant fluid or transmission fluid is passing through. Have this immediately investigated since neglecting it may cause worse damage to your vehicle. Take your I-370 to the local dealer or an expert mechanic for proper inspection and repair.