Originally Posted By: ak62sporty
The vehicle has an intermittent no start/ rough run condition. Everything was fine until I had about 7,000 miles on the car. Then one day it picked up a multiple cylinder misfire with a flashing check engine light. The dealer claimed it was due to dirty oil. As per the owners manual, I was waiting for the change oil light to change it. I had the dealership change the oil, they put in 5w20. The owners manual quoted above is different than what came with my car, the acceptability of 5w20 is not quantified with 'temporarily' in my edition. I did not ask for the 5w20, I simply trusted them to use the correct oil. This was in October, when it started to get colder. After the oil change, the problem continued to occur. Several times while driving it would pick IP a horrendous misfire, bad enough to make the car underivable. 3 other times it failed to start in the morning and got towed into the day dealership. The dealer did nothing to diagnos the vehicle, claiming they can't fix it with no codes. Twice when I went to pick vehicle up after they said it was repaired, it wouldn't start. After I began the lemon law procedure, the dealership has one chance to make a final repair, under Alaska law. The dealership, after working with the factory, used their last chance to change the oil to 0w20. I picked the car up yesterday, and am now driving and waiting for it to leave me stranded again. I posted here as I am curious about more knowledgeable opinions on their explanation. I put little faith in it myself, but don't have the technical knowledge on oil to know for sure.
The misfire condition has occurred on both 0w20 and 5w20 oil, so it is not the cause of the problem. The dealer is just putting up a smoke screen. If the oil was affecting the cam phasers, that would not cause a misfire condition. Problems with the cam phasers would cause fault codes to be logged which the service department could then read.
I find it to be very fishy that they have failed to read fault codes after the Check Engine light has been flashing. In my Camaro, if the Check Engine light comes on, a fault code will be in the memory, even if the problem is intermittent. I have my own code scanner, and it classifies faults as active or inactive.
After reading about the process you have gone through so far, I take back what I said in my previous post. It does seem time to invoke the Lemon Law.