So, wanted to start a thread for weird/odd/unusual issues people have had with their vehicles and the strange thing that caused them, which you wouldn't expect.
For example, the g/f's car (2013 Honda Fit) was getting an exhaust/fuel smell in the cabin when sitting idle. It progressively has gotten worse over the last few months. Last week I got the car up in the air and checked the entire exhaust system, of what I could see, for cracks/leaks/etc, and found nothing. Couldn't see the exhaust manifold because it was above the front crossmember and heat shield. Oxygen sensors were good as well.
Opening the hood while it was running you couldn't smell it from the front of the engine bay or driver's side, but could smell it on the passenger side and rear of engine bay. Went down the interwebz rabbit hole for others that had similar issues. All kinds of suggestions were given, but were primarily focused on the issue manifesting after a modification was made. In this case, the car is bone stock with only 77k miles on it.
Well, after going further down that rabbit hole I saw that someone suggested checking the plugs, as they are sometimes known to back out on their own. I'm thinking, "no way a plug is going back out after just a few years and 77k miles", so moved on to checking other things. Well, that and because getting to the plugs kinda sucks. The plenum on top of the engine blocks view/access to all plugs except for the one closest to passenger side, calling that #1.
Last night took apart the lower windshield cowl and its under tray so I could get to the coil packs and the plugs. Took off coil #1 and it looked fine, not exactly brand new, but in good shape. Proceeded to #2 and the boot was filthy, covered in residue, same with #3. Coil pack #4 looked the same as #1, so the outer cylinders were fine, the inner were looking pretty bad.
So now I'm thinking the loose spark plug thing isn't so cockamamy and might have some truth to it. Pull plug #1 and it's fine, just normal wear. Pull #2 and holy shit is it bad, so is #3. When I had the socket on #2 and started to loosen it there was no resistance. I thought maybe I wasn't on the plug, so I stopped. I then turned it to tighten the plug and counted the half-turns till the crush washer made contact.
#2 was seven 1/2 turns (3.5 full turns) from making contact and #3 was eight 1/2 turns (4 full turns) from making contact. That doesn't include the fact they're supposed to be torqued to 12-13 ft lbs. Well fuck me. I had never seen spark plugs back themselves out before. I can say at least they were gapped correctly at 0.050".
The crazy thing is no error codes or CEL were present. Just a rougher idle, less power, and worse mileage. She drives the thing with a heavy foot so didn't think much about the bad mileage (getting mid-upper 20's when it should be low 30's).
So here are some photos I took:
L-R (passenger side to driver side) 1 - 2 - 3 - 4 (new Hitachi replacement at bottom)
And here with their corresponding plugs.
Close up of #2 (left) and #4 (right):
For example, the g/f's car (2013 Honda Fit) was getting an exhaust/fuel smell in the cabin when sitting idle. It progressively has gotten worse over the last few months. Last week I got the car up in the air and checked the entire exhaust system, of what I could see, for cracks/leaks/etc, and found nothing. Couldn't see the exhaust manifold because it was above the front crossmember and heat shield. Oxygen sensors were good as well.
Opening the hood while it was running you couldn't smell it from the front of the engine bay or driver's side, but could smell it on the passenger side and rear of engine bay. Went down the interwebz rabbit hole for others that had similar issues. All kinds of suggestions were given, but were primarily focused on the issue manifesting after a modification was made. In this case, the car is bone stock with only 77k miles on it.
Well, after going further down that rabbit hole I saw that someone suggested checking the plugs, as they are sometimes known to back out on their own. I'm thinking, "no way a plug is going back out after just a few years and 77k miles", so moved on to checking other things. Well, that and because getting to the plugs kinda sucks. The plenum on top of the engine blocks view/access to all plugs except for the one closest to passenger side, calling that #1.
Last night took apart the lower windshield cowl and its under tray so I could get to the coil packs and the plugs. Took off coil #1 and it looked fine, not exactly brand new, but in good shape. Proceeded to #2 and the boot was filthy, covered in residue, same with #3. Coil pack #4 looked the same as #1, so the outer cylinders were fine, the inner were looking pretty bad.
So now I'm thinking the loose spark plug thing isn't so cockamamy and might have some truth to it. Pull plug #1 and it's fine, just normal wear. Pull #2 and holy shit is it bad, so is #3. When I had the socket on #2 and started to loosen it there was no resistance. I thought maybe I wasn't on the plug, so I stopped. I then turned it to tighten the plug and counted the half-turns till the crush washer made contact.
#2 was seven 1/2 turns (3.5 full turns) from making contact and #3 was eight 1/2 turns (4 full turns) from making contact. That doesn't include the fact they're supposed to be torqued to 12-13 ft lbs. Well fuck me. I had never seen spark plugs back themselves out before. I can say at least they were gapped correctly at 0.050".
The crazy thing is no error codes or CEL were present. Just a rougher idle, less power, and worse mileage. She drives the thing with a heavy foot so didn't think much about the bad mileage (getting mid-upper 20's when it should be low 30's).
So here are some photos I took:
L-R (passenger side to driver side) 1 - 2 - 3 - 4 (new Hitachi replacement at bottom)
And here with their corresponding plugs.
Close up of #2 (left) and #4 (right):