civic 1.5 engine problem

[keriazy4]

hi everyone if someone can tell what problem i have in my car
started in a day when it was -30c and i was on the hightway runing about 110km/h then one time i felt the shifting knob is shaking ,the same feeling like there is a spark plug not working and the car going on 3 spark plugs, so i check them and i found oil on 2nd and 3rd spark plug, i cleaned everything even changed the Valve Cover Gasket Set , installed every thing back in place but still doing the same thing .
not all time only when i reach 70km/h on 4th and 5th depend specially when im going on a bridge ,at 80km/h it return no shaking again
1st.2nd.3rd has no problem at all with smooth shifting or burning and the engine gives good power also
so what is that and why exactly at 70km/h ??
my car has 256000 km
thank you

[Rhubarb]

Hi and welcome.

Your problem is occuring under load, so it will be either down to the spark plugs, ht leads, coil packs/ignition coil in that order

[sorted]

Not the easiest post to follow but if I am reading it correctly it happens when you get to 70 but then clears when you get past 80kph? And it pulls strongly and smoothly? just wondering if the shaking is nothing to do with the engine but maybe wheel balancing or something

[keriazy4]

ok so its related kind of the engine electrical system ,i thought it will be a problem with vales or cylinders,maybe the transmission gear ..
thanks for replaying

[Deleted]

Vehicle speed sensor signal !!