平成19年　三菱　デリカ　エンジン異音修理ー１

A 2007 Mitsubishi Delica has come in for engine noise repair. The owner said that a gas station told them there was an engine oil leak and that the engine was making a strange noise, and asked them to have it checked. They also mentioned a whining, motor-like sound when driving. Indeed, there is a whining sound when driving. The noise doesn't occur when revving the engine at idle, so it's probably not coming from the pulley. Occasionally, there's a noise from the pulley under load, but that's not the case here. I'll check it by driving. The sound gets louder when the accelerator pedal is pressed. There's also a rumbling sound from the rear, but I think that's tire noise. I'll also check the hub bearings for play and any other noises later. The noise the owner is concerned about seems to be the whining motor sound. Could it be a noise from the CVT? The owner also mentioned that at the gas station, after having their tire pressure adjusted, they were told that the right rear tire pressure was too low and it might be flat, so they asked me to have it checked. I think a flat tire repair would be something the gas station should check. I'll check the right rear tire for a puncture. It doesn't look like there are any nails or anything stuck in it, so I'll remove the wheel. Spraying soapy water, I can see a slight leak from the air valve; the tire and rim are fine. I'll replace the air valve. I removed the tire from the wheel and replaced the air valve, but it seems the leak was coming from the base of the air valve due to corrosion on the aluminum wheel. I cleaned the air valve mounting area on the aluminum wheel and replaced it with a new air valve, but it might leak again. Currently, checking with soapy water shows no air leaks. I'll inform the owner. I reinstalled the wheel and checked the hub bearing for play and any unusual noises; it seems okay. Once the car is on the ground, I'll tighten the wheel nuts. I checked the left rear hub bearing for play and any unusual noises; it seems okay. The humming noise is to be expected with studded tires. I'll check for any unusual engine noises. I checked the engine oil level; it's low but OK. Before suspecting the CVT, I'll check the intake pipe. It's definitely torn. Air might be getting in from here, causing the noise, so I'll replace it. The engine oil leak seems to be coming from the valve cover. I'll remove the intake pipe. While working, I noticed the air cleaner case rattling, so I'll inspect it after removing the intake pipe. It rattles when I remove the air element, but there are no cracks, so I'll put it back together. If the intake pipe wasn't torn, the air cleaner case wouldn't rattle. This is where it's held in place, so perhaps the Delica's intake pipe is prone to tearing. I'll order the parts and call it a day.