I have a 2004 (Ecotec obviously) Sunfire with about 168,000 miles on the clock. More and more I have noticed it burns oil like it is supposed to run on it. I have to add a quart about every 400-1,000 miles. I have noticed the time between top offs seems to decline as the oil gets older and dirtier. I have also noticed small amounts of oil on the inside of the air intake tube, assuming it it getting sucked in from the valve train. I use 5w30 conventional pennzoil religiously. I want to know if anyone else has encountered this problem and what your preferred oils are. Would stepping up in weight slightly (to 10w30) possibly slow/stop the consumption? Thanks in advance!
2004 Sunfire, 2.2L Ecotec, 5sp.
Tony C, I too also have that issue. I use 5w-30 Valvoline Sythetic for high mileage cars... Just started to notice my car drinking oil quicker than my S2000 around 120k miles.
Take careful note of the tailpipe when you start the car after it has sat for a while, like overnight. Could have some leakage though the valves. With it coming through the intake tube, I don't recall if the stock manifold has a PCV that can be serviced but I might start with making sure the passages are clean. Could have excess oil in the valve train from a partially blocked return passage. If you haven't doing a good SeaFoam treatment and/or pull your valve cover and check the return ports for build up. In the mean time, like you mentioned, moving to a 10-30 could help a bit but depending on where you are located (in the frozen north for instance) you may want to wait until warm weather before switching to heavier oil.
Thanks Sparkey, I never thought about checking the PCV ports, I have a 03 Cavalier with 89,000mi on it, I also have the same problem. I have been running 10W30 along with Lucas in the car lately and it has slowed the consumption down. I have to add roughly a quart every 1000 mi and I have been changing the oil every 3000mi. I also noticed that the tail pipe and bumper around the tail pipe is covered in black soot after about a day of driving the car. When a bought the car last June it only had 65,000 mi on it, the oil fill cap and dip stick were gummed up good, so I'm sure the PCV ports are as well.
Ok, after a little more research this seems to be a common problem with the Ecotec engines. the PCV port is located in the intake manifold not the valve cover. if this port is clogged that will allow crankcase pressure to build allowing ether blow by or oil in the PCV vent tube. see attached thread.