undulating power
 

hi , got another wee question , in my 964 T if i cruise along at aroud 2k rpm and hold it steady there seems to be an undulation in the power/rpms ie goes up and down but only a tiny amount - its quite annoying when driving has anyone any idea what could cause this ? other symptons it would have is if you rev it from idle there is like a hiccup as the revs increase around 1-2.5k when blipping the pedal , also it seems to idle slightly low - 550-600rpm

ISV ? - could this cause both issues ?

any help greatly appreciated ?


cheers

Johnny

Johnny,
Try tightening all of the intake manifold nuts, that helped me once.
Also, it could be a bad O2 sensor, but those seem to fail rich and your symptoms sound like a lean condition. Finally, check your injectors with the six baby food jar method. If you don't know that method, just post again, many here can help you.

Mark