Ok , first of all I've got a JDM S5 TII with a rebuilt motor about 5000kms ago. Everything is stock except for a street/extend port and pod filter.

I've replaced then spark plugs and ignition leads recently so highly doubt they're the problem.



Occasionally when I'm driving along at a constant speed the car starts to jerk violently. The only way to stop it is to accelerate or take my foot off the throttle.

It feels like I'm stabbing my foot on and off the throttle.

It seems as if there's an intermittent ignition problem in one of the rotors so it will fire, then not, then fire, then not etc. all within a moment. It had slowly been happening more often.

I've checked to see if the connections of the leads to the spark plugs and coils were loose.



Any help please guys. I'd rather fix this myself than take it to a shop to get fixed.

bad igniter box?

i think its more likely to be a bad o2 sensor, or tps

Really would and o2 cause it to be that bad?

I've been having the same problem with my car for a few months. so bad now that I have to pull over on the highway. it would jerk and jerk to the piont that it would travel so slow I'd have to pull over and let traffic by me. you sound like me about two months ago. hope you aren;t headed where I am with it.lol......I think. I'm in the middle of a major overhaul I'll post pics soon. https://www.nopistons.com/forums/pub...IR#>/smile.gif

crusing is the only time the ecu really uses it, so if its off, it can do weird things.

just for the hell of it play around with the tps and see if it goes away... and if it changes or whatnot set it at the proper setting and you should be good to go...

It's stopped doing it now. I'm waiting for it to come back and get worse. Then I'll have a look at the oxygen sensor. I was thinking it could be the TPS but that should have been set correctly when the motor was rebuilt.

I bought a Bosch oxygen sensor to put in but haven't installed it yet. Is there any difference between the mazda and bosch O2 sensors? Is installing it just a matter of disconnecting the old one, unscrewing it and putting the new one in?

personally i wouldnt use anything that was stamped Bosch i have seen their spark plugs just fall apart (ceramic part in it gone) in someones engine