This 99 civic lx I just got died suddenly and wouldn't start back up. Killed the battery so I lost the codes (if there were any pertinent to the problem) and so I started troubleshooting. Checked main power relay, did resistance check on all the dizzy sensors, coil, ckf sensor everything tested good. Was getting injector pulse, but no fire from the timing gun. Figured it must be the ecu, so got one to check. No dice. For some reason I thought to try advancing the timing to get it to start as I have had a bad ckf and got it to start that way. Started up, set timing back within tolerance and it runs a bit rough. Hit the throttle and it instantly dies. Had to advance timing to get it to start again. Swap out ckf and tdc, no change. Old timing belt so I figured maybe stretched, new one, no change. Running out of ideas. I'm borrowing a whole different dizzy tomorrow to test it with, but I'm hoping someone has some good advice. Checked the computer while starting and running, electronic timing advance is only showing 20-25 advance, and it will run in standard settings at that.
I let it sit and run for a while hoping it would throw a code that would be helpful, but no. Advanced timing belt for kicks and giggles, starts but ticks a bit and runs worse, still has no throttle response. Computer is showing 8.2% throttle when closed which is not unusual, and does change with movement. Tried temp sensors (read of them causing extreme timing adjust by computer due to showing extreme temp), map sensor, running it on carb cleaner and anything else I could think of. I don't care how hair-brained you think an idea is, run it by me, I have way too many hours in this thing and it still doesn't run.

 

Sounds like the timing belt skipped a tooth. Is the mechanical timing set perfectly at TDC1?

 

Thanks for the quick reply. I have checked the belt timing before and after I replaced the belt, including checking it at the oil pump mark in case the ballancer key has been compromised. I even advanced it a tooth to be sure, as I stated in the first post. That is when it started but ran even rougher and it actually threw every misfire code available when I did that, which it didn't do on the correct mark.

 

I have also checked the dizzy and sensor wiring at the ecu. Resistance and short tests, which all came up good.

 

Check the ignition timing? With a timing light?

 

Once I get it started, ignition timing checks fine. But until I advance the dizzy 1/8 turn our so to get it started, it has no fire.

 

Finally got it! Swapped the dizzy with a known-good one and bam we have a good running car! Thanks again for the time and ideas fellas.

 

guarantee that it was the ignition coil thats inside the dizzy.

 

Ok, not sure how you see a bad coil that will run when advanced, but you are welcome to you're opinion. I'm thinking cyp sensor.

 

I agree, or TDC sensor circuit. No CEL code? Did you test it or the two wires?

 

No cel, I did check the two wire as well when I checked timing. I thought tdc, but changed it with one I thought was good, but not for sure.