This is a family members car that was purchased used with 221K miles. It has the Toyota 1zz-fe engine. It ran good and the interior/exterior looked nice, as if it had been well cared for. The idle seemed a little rough so I changed the air intake gasket. That fixed the rough idle. While removing the intake I saw that the pcv valve and tube was caked with sludge.
I changed the oil/filter used 1 qt kerosene (left running between 10 minutes to 1/2 hour) a few times. I used cd2 detergent once then kerosene and changed the oil and used risolone and then added kerosene and changed the oil. I cut a couple of the filters open and while they had trapped some debris, it wasn't too bad. Last oil/filter change was at 222970.
I had some time a couple of days ago and removed the valve cover, miles were 222992. The valve cover, head and cams were covered in hardened burnt oil and sludge. I cleaned off as much as possible. I used a shop vac in one hand and a screw driver in the other to carefully remove the deposits and suck them up at the same time. after cleaning as much as I could I used a toothbrush with some kerosene. I used air to try and blow out as much gunk as I could that the vacuum missed. I added a quart of kerosene and put it back together. I started the car up and it ran for about 30 seconds and the oil pressure light came on. I stopped the car and decided the light came on due to sludge in the pan.
I pulled the pan and sure enough there was enough sludge to cover the pickup. I cleaned the pan. removed the pick up and cleaned it. I cleaned much of the sludge from the bottom end.
Everything was put back together. Filled with pyb and a fram ph3600. I started it up and no more low pressure light. It runs great. My plan is to run it about 2k miles. Then I will use Pennzoil platinum (because of price)and a fram xg3600 for a 5k mile oil change interval. I'll update next year at this time with pictures of the bottom end and under valve cover pics.
I would definitely say that the sludge was caused by improper maintenance. The pcv valve maintenance was ignored. I'll bet the oil change intervals probably weren't as recommended. I wish I had taken pictures before I used the kerosene.
I changed the oil/filter used 1 qt kerosene (left running between 10 minutes to 1/2 hour) a few times. I used cd2 detergent once then kerosene and changed the oil and used risolone and then added kerosene and changed the oil. I cut a couple of the filters open and while they had trapped some debris, it wasn't too bad. Last oil/filter change was at 222970.
I had some time a couple of days ago and removed the valve cover, miles were 222992. The valve cover, head and cams were covered in hardened burnt oil and sludge. I cleaned off as much as possible. I used a shop vac in one hand and a screw driver in the other to carefully remove the deposits and suck them up at the same time. after cleaning as much as I could I used a toothbrush with some kerosene. I used air to try and blow out as much gunk as I could that the vacuum missed. I added a quart of kerosene and put it back together. I started the car up and it ran for about 30 seconds and the oil pressure light came on. I stopped the car and decided the light came on due to sludge in the pan.
I pulled the pan and sure enough there was enough sludge to cover the pickup. I cleaned the pan. removed the pick up and cleaned it. I cleaned much of the sludge from the bottom end.
Everything was put back together. Filled with pyb and a fram ph3600. I started it up and no more low pressure light. It runs great. My plan is to run it about 2k miles. Then I will use Pennzoil platinum (because of price)and a fram xg3600 for a 5k mile oil change interval. I'll update next year at this time with pictures of the bottom end and under valve cover pics.
I would definitely say that the sludge was caused by improper maintenance. The pcv valve maintenance was ignored. I'll bet the oil change intervals probably weren't as recommended. I wish I had taken pictures before I used the kerosene.
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