Echo Misfire problem

[masterofservants]

Hi there!!! I have an 2001 Toyota Echo not firing on a cylinder check engine light on. So I scanned it found p0303 code cyl #3 misfire. I swaped coils with #2 cyl. and the code jumped to #2 misfire. I obviously assumed that I had a bad coil. I replaced the coil with a new one (same part# ) it runs smooth now but only for 10 seconds and the whole [COLOR=green ! important][COLOR=green ! important]car[/COLOR][/COLOR] shuts off. I put the old coil back in and it runs but it still misses. Checked resistance on new coil and one of the other coils was different so I bought all new coils and it does the same thing runs nice and smooth but for only like 10 sec. So I started from begining checked for spark on bad cylinder no spark but I am getting injector pulse and 12V and 5V signal from ECM. Put new coil back in checked for spark. Now I have spark installed plug and new coil runs smooth for 10 sec and shuts off. I cleared codes disconnected battery thinking of way to maybe reset the ECM. I know that its just a coil but not sure why it now just cuts out.

Any help would be greatly appreciated!!

Thanks, Jason

[caveatipse]

After only 7 years that is not good. Can you just replace all the coils, spark plugs, and plug wires? That might work. If not then it is probably a computer problem.