My girlfriend has a 2000 Mazda Familia wagon 1.5 ZL that is giving weird issues.
Basically the car was stuttering at low speeds and hesitating then taking off once you reached about 4000rpm.
I replaced the filthy air filter and sparkplugs, which seemed to make a difference to the stutttering.
But the car still feels like it is hesitating struggling to breathe/go under 4000rpm. It has no go or power (even for a 1.5L) but once you reach over the threshold, it picks up and flys in comparison.
Even when the car is stationary and you rev it the car will not freely rev until over 4000rpm. Even with no load it is sluggish and hesitant in how it revs at low rpm.
Any ideas on what I could check?
Its got me stumped at the moment...because it is also somewhat intermittent.