Hello folks,
Sitting at a red light in my 2002 Z24 the other day I noticed what I thought to be a slight tapping or knocking noise coming from the engine. I turned down the radio and listened closely, but couldn't hear anything distinctive and figured it was just a piece of plastic rattling in my dash (it's cracked all over the place). The next day I hopped in my car to run some errands before class only to notice a horribly loud tapping noise coming from my engine bay. It's constant and even paced, I can hear it clearly from outside of the car and even inside while idling. The noise increases evenly with engine RPM, but isn't really noticeable at RPMS above 3000 because of my exhaust and road noise. No noticeable decrease in power and doesn't seem to be affected by engine temperature.
Here's a video:
Here's my problem. I'm currently 100+ miles from home as I'm currently in college. Every day I make the 2 mile drive onto campus and back. My family owns a repair shop in New York and thankfully will fix whatever this is for next to nothing. The problem is the 100 mile journey I'm going to have to make later this week. I've sent them the exact video above and while they're not sure, they seem to be fairly confident that it's not Rod Knock; although I've made them aware it's quite common in the LD9 (Rod #3). After speaking with the shop some more, they convinced me to, against my better judgement, "run the snot out of it". I reluctantly got into my car, thinking that this may be my Cavy's last hurrah in what should be a spectacular death on the on-ramp to I-80 West. As I got nearer to the highway, my engine reached optimal temperature (I wouldn't do this cold, I'm not silly). A vicious 3rd and 4th gear sprint onto the highway all the way up to 5500 RPM with no signs of letting up. The car pulled as good as the day I bought her. As I pulled back into my parking spot, I rolled down my windows and to my surprise, the tapping noise was much much quieter. I don't get it..
So my questions are:
1. What can this noise be? I'm starting to think (or at least hope) it's a bad lifter.
2. If it is indeed a bad lifter, is it bad to drive with one?
3. Is it safe to drive 5 miles a day? I cannot miss a whole week of classes. If so, what about the 100 mile trek back home? The shop has tow trucks, but I'm reluctant to put that kind of financial pressure on my family business.
Thanks in advance,
Alcolawl
Guess there's no edit option?...
Car details: 2002 Cavalier Z24 2.4L 160k miles. I've put about 3000 miles so far on Synthetic oil. I've checked the oil and color, both look good.
Sounds like mine did for a year. Then it got really loud and I am pretty sure it was wrist pin or something. Mine only knocked under load though and I pulled then engine the day after it happened and swapped to an ecotec.
On the inside my car looks like a fighter jet.
Rob Dotterer wrote:Sounds like mine did for a year. Then it got really loud and I am pretty sure it was wrist pin or something. Mine only knocked under load though and I pulled then engine the day after it happened and swapped to an ecotec.
Still a better love story then twilight!
Got the car back to New York in one piece. Got her into the shop and my step dad, mechanic and I stood around listening to the knock for a bit, trying to identify where it was coming from. After confirming that it was coming from the top of the motor, we tore into it. To our surprise, upon taking the valve covers off, the engine looked immaculate. I mean perfect. No defects, scratches, shavings, nothing broken or out of whack. We were stumped. I got a ride back home as it was about time to close up shop but they worked on it for another day or so before figuring out that it was the Timing Chain slapping against the side of the housing because the previous mechanic installed the tensioner wrong. So all is well!
Check under that cover.. the coils cover and see if its cracked...
Good to hear you fixed it.
Just for your own information I'd like to say in general if a car is making ticking noises like that it doesn't hurt to take off the valve cover and look inside. Valve train stuff isn't that hard to check if its out of adjustment.
