Juddering

[SilverWitt]

my lexus ls 400 misses between 40 and 50 but is perfect apart from that . just changed the plugs but hasnt cured it

[SteveLS400]

my lexus ls 400 misses between 40 and 50 but is perfect apart from that . just changed the plugs but hasnt cured it

Hi SilverWitt and welcome to the forum. The search facility is a massive resource, so start there using terms like "juddering", "plugs" and "missing" and plough through the results. Try other terms as well if the results aren't helpful.

Also, when you come back to here, let us know more info such as year and MK (I,II,III or IV), when the symptoms started ie after, type of plugs and as much more as you can think of to make a diagnosis easier. Have you checked the leads for tracking. What about rotor arm?

When you do the search you should find the procedure for determing the fault code using a paperclip. Come back and tell us how you are getting on.