My mom and step dad have an 05 Aveo that they purchased new. It has the 1.6 Ecotec and auto trans, car has approx 50,000 on the clock. History of the car is that oil was changed between 3 and 5k and anything else was replaced as it went bad basically. About a year ago it threw the timing belt and the valves, head, and belt was changed under warrenty by dealership. 6 months ago I changed the plugs, air filter, and oil.
Now that thats out of the way. Day before yesterday they are on their way back home from somewhere and the "hold" and "CEL" started blinking and car began running rough. My step dad pulled off the road and shut the car down and had it towed back to their house. I stopped in after work last night and took it to AZ and had codes read, and code P0300 pops up. This is the only code. So its a random multiple cylinder misfire (no kidding right lol). I see no arcing from spark plug wire, I am yet to pull plugs. When touching vacuum lines I noticed that they are real brittle and crumbly, but I cant hear air anywhere and I do hear sucking when I pull each line off. Other problems could be the coil pack, EGR, high/low fuel pressure (filter is going to be checked tonight), and injectors.
I am of the mind that all 4 injectors wont go out at once and if one does go it will cause 1 cylinder misfire, same with plugs and wires, which leaves the coil and EGR. Anything else to check for? Am I totally off base and how would I check/test some of these things? All I am working with besides tools for test equipment is a multimeter and a prayer. I appreciate any help that can be offered. If this was my car I would test and have no problem replacing a part/sensor whatever, and if that wasnt the whole problem, move on to the next. My folks do not have money like this though, and my car would be in my driveway and not an hour away. TIA again.
Now that thats out of the way. Day before yesterday they are on their way back home from somewhere and the "hold" and "CEL" started blinking and car began running rough. My step dad pulled off the road and shut the car down and had it towed back to their house. I stopped in after work last night and took it to AZ and had codes read, and code P0300 pops up. This is the only code. So its a random multiple cylinder misfire (no kidding right lol). I see no arcing from spark plug wire, I am yet to pull plugs. When touching vacuum lines I noticed that they are real brittle and crumbly, but I cant hear air anywhere and I do hear sucking when I pull each line off. Other problems could be the coil pack, EGR, high/low fuel pressure (filter is going to be checked tonight), and injectors.
I am of the mind that all 4 injectors wont go out at once and if one does go it will cause 1 cylinder misfire, same with plugs and wires, which leaves the coil and EGR. Anything else to check for? Am I totally off base and how would I check/test some of these things? All I am working with besides tools for test equipment is a multimeter and a prayer. I appreciate any help that can be offered. If this was my car I would test and have no problem replacing a part/sensor whatever, and if that wasnt the whole problem, move on to the next. My folks do not have money like this though, and my car would be in my driveway and not an hour away. TIA again.
