Weird wierd wierd 306 problem!

Hi
Having some problems with my 306, its a 1.4 1997 model.
The idle speed varys without me touching it, while im driving it when i take my foot off the accelerator it backfires as the revs go down.
The worst thing it does is when I put my foot down past a certain point I loose all acceleration and it starts misfiring like crazy. It sucks when im pulling onto a fast road and it takes ages to accelerate:(
Ive had the Lambda sensor changed cos there was an error on the computer with that. There arent any errors on the ECU now, I checked and cleaned all connections to the sensors and the ecu, changed the spark plug leads and checked the spark plugs.
Help!

Check which system your coil pack is.

Also the idle varying problem is usally the stepper motor or lambda or oxgygen sensor.

back firing sounds like overfueling, get it checked out m8.

cheers m8
Maybe all the garages are useless round here cos they say they cant find anything without trying loads of bits
I'm not sure if the idle is varying or just occasionally misfiring, its just isnt smooth know what i mean?
I was thinking distributer, its the last thing in the ignition system I havn't checked really...

distributor is the coil pack if i am thinking right.

Theres one type which is prone to problems, think its bosch but not sure.

ok thanks I'll look

check the injectors and the throtle valve it's a common problem where you get a build up of crap around the throtle butterfly valve where the air box fits. take the airbox off open the valve and clean with degreaser. works every time when mine plays up.