The thing about my 1996 Z24 Cavalier with the 2.4l "Quad Four" was that the Oil Pump went out on it and I never knew b/c there was some kind of electrical shorts going on that made all the lights on the dash always on like a Christmas tree. So even the "dummy light" couldn't save me. What's worse is, I had the engine rebuilt only to have it fail again in a few months. Then paid a friend to rebuild it again and it ran for awhile until once again, there became this HUGE rod knocking sound. So I just sold it. The guy who bought it went to rebuild it and found it had a bad oil pump and that was the problem all along.
I wish my original rebuilder's would have caught this... or the subsequent re-rebuild guy. Instead the just bought the crank kits and rebuilt them using all the old parts still available, so it was never caught.
The thing is, that engine was tough as nails. If it wasn't for that oil pump being bad (without me knowing for a great deal of time I suspect) it would still be kicking just fine now.
I spent a ton of money having it rebuilt twice. I spent a ton of money on it. I just bought Goodyear Eagles all the way around, and since it was 4 wheel independent suspension I went to AAP and bought the Monro Sensatrac complete suspension kit (almost $ 1,000) that literally you just unbolted the entire suspension and put in an all brand new everything in under the fender-well. I also replaced like everything (other than the oil pump, lol) like the battery, alternator, coil packs, plugs, catalytic converter, water pump, radiator, all hoses and belts, and numerous other things. All in an effort to get it reliable for my daughter as she was going off to college. Ended up she bought herself a new 2010 Cobalt after that Z24 kept breaking.
It sucks so bad to have so much money and time in a car for it to keep blowing and eventually to find out it was just an oil pump that was bad that none of the rebuilder's ever managed to check I guess. I loved that car too! I bought it in 1998, and though I beat on it like a red headed step child cause the car ran hard and was pretty swift, it would always just keep on keeping on. My dream, b/c the car was pretty fast stock, as most quad 4's were, was to upgrade it with a turbo someday and to basically put it in the garage to work on as a project car. This car got me back and forth to work day in day out never failing for over a decade. And I never checked the oil, always ran the oil like 8k+ miles on cheap dino that whoever had the best sale going (usually wal-mart).
I once drove it without oil even showing on the dipstick for over 20 miles to get to my brothers house, who had some oil at his house as I was too broke to buy any. It did it no problem. I know I should have taken better care of it, as I do my cars now. In fact, it's b/c I loved this car so much and I abused it and ended up losing it that I came to FINALLY learn my lesson and start taking care of my vehicles. Now I check the oil on my car daily and my wife and daughter's weekly. I learned a lot from BitoG and now I'm at the complete opposite end of the spectrum and am overly anal about preventative maintenance and most especially the oil's.
One day, I hope to buy a very well taken care of 1996 Z24 and pull it in the garage and tear it all down to the bones and slowly, over time, build it all back up to perfection. Rebuild the motor with some nice quality aftermarket parts (nothing overly powerful, think more of high quality, long lasting, better MPG's and more power). I'd love to see what a true 2.4l Quad Four engine could do when built and turbocharged, as the stock engines are quite fast already! I suppose I would need to lower the compression so I could run higher PSI on the Turbo but I'd imagine it would be quite quick!
