ka24E massive backfire

[dat925stunna]

ok once again i have a 90 hatch im running an auto ecu and also open header becuz my cat was clogged my exhaust was actually rigged up by the previous owner so normally the cat bolt back on but in my case its all welded so i cut it off and every now and then my car will drive fine then sputter like i cant drive stick its so embarassing wen im with my GF omg is it the ecu failing me or my open header idea .... cuz iam swapping this motor to an LS1 but im waiting to re-smog with the stock ka so i doit the legal way any input would help?

[dat925stunna]

bump

[Klits562]

i would probably go with blaming your cut off exhaust, without the cat and with very little exhaust your gonna get massive backfire and maybe the reason your car sputters is from the lack of back pressure from your exhaust.... seeing as its not there anymore

[zachattack_5491]

Check your timing for the backfire. Might have something to do with your sputtering issue also. Does it sputter just whenever, when its cold, hot?