Hi,
On my 1991Corolla, 4A-FE 4-cylinder, the engine turns over with little noise, so I suspect no compression due to a bad timing belt. I checked for compression and their is none, checked for spark, none as well. It seems like a timing belt issue, but I am not a mechanic, (just die hard DIY). What bothers me about my diagnosis is how the problem unfolded; i.e. don't timing belts go bad when you have the engine running/driving, etc and not after the car has been sitting for hours? Plus when it goes, doesn't it fully fail, without out warning? In my case I noticed the problem as I started my car after I got off work (after it had sat for 9 hours), something seemed way wrong, (no compression) then after 20-30 seconds of cranking where it sounded as if there was no compression, it came back to "life;" i.e. sounded like it normally does when cranking and then started up. On the drive home, I made a 1/2 stop and the engine restarted fine and I also turned off engine at some point to see if it would start, which it did. Then the car sat over night and the problem was there again when I tried to go back to work, and will not start up for good this time. Hence with that slight amount of intermittent failure, does that point to something else (and hopefully easier to fix) or is that typical of a timing belt failure? And if not the timing belt, what else could it be?
Thanks for your help.