my car is a 92 FD3S no engine mods except an apexi air filter. the problem i have is that once the car is warmed up the engine idles at around 1200rpm and the needle keeps movin up and down between 1200 and 1400 rpm with the engine revvin with the needle. just recently started doin this and does it all the time now.
please help me!!
Cheers
Carl

 

Check and verify a couple of things
1) Vacuum leaks can cause this
2) TPS may need adjustment
3) If the throttle plate initial setting is too large, it will also cause this

Finally, do a search on pulsing idle or hunting idle and you will find lots of stuff to read about the problem you're having.

 

hey thanks for the reply. how do i adjust the throttle plate initial setting? and how do i adjust the tps? cheers
Carl

 

There are on-line factory service manuals for our cars. Look under the FAQ thread in 2nd generation. Details for all kinds of adjustments are in there. There are two or three methods for checking and adjusting TPS settings....twin test light, Resistance at the connector and voltage at the ECU. Search for TPS adjustment and you'll find details.