Depending on where you drive / live, what mileage you do and what induction set up you got. My bet is it needs a good clean out.
If you live in a buit up area air polution can be greater and although its not much over years fine carbon particles in the atmosphere build up to create alot of sh!t in ya engine.
If you do more mileage the chances of this happening increase.
If you have a K&N or similar filter fitted you are suckin in more air = more polution. Although the K&N and similar filters have very good filtration the volume of air intake is greater and carbon build up will occur quicker.
When i bought my car she had done 50k mainly poodling round south London. She was idling badly and lagging on pickup, even stalling in low revs. Cleaned out the induction system and the throttle body and the difference was astounding. Like driving a brandnew car. Instant responce and perfect idle.
My advice is, take out the induction system and clean it all out, replace the filter if necessary. I use a K&N pannel filter.
Dismantle and clean out the throttle body. This takes about an hour and a half to do properly, i used a peice of fine cotton rag, some carb cleaner and some WD40. If you use the WD40 last and wipe it all clean it should leave a nice friction free film, helping to protect and limit carbon buid up. Could be Bo!!ox but makes me feel better. Follow the Haynes instructions on getting it apart and back together again.
Give it a try, hope this helps!
