[vinny55]

My 1998 sephia just started running so bad you could barely get the thing over 20mph. Spitting and sputtering with the cel on. I found your forum and started reading through it and it seemed alot of problems like that were plug and wires, so i tested them with a spark tester and they sparked. Finally I bought the wires and put them on and that was it, runs great. My question is why would the spark tester that you attach to your plug wire show they were good if they weren't. Thanks

 

[97molavi]

Simply having spark is not good enough. You might have crappy/borderline spark. But the plug might be performing %10 and the wires might be cracked with high resistance. Either way have the CEL codes read at autozone, since it seems you have been overdue for a tune-up. You might still need new airfilter and O2 sensors.