Hi guys,sva retest thursday 26th so heres hoping.
Over the last 3 weeks I have had a prob with wifes 25-when started it runs fine and then after about 25 secs or 300m it will either idle rough(putting out exhaust and rocking block on mounts)or if moving will choke up dragging revs down and bringing car to a crawl in any gear.The only way to cure it is switch off and start again -and hopefully things will be clear this time -or rev to over 3000 and suddenly problem will clear-after this initial prob car runs fine-until u next switch off!
Not plug leads and happens when hot or cold ,wet or dry,full fuel tank or empty.
Has been on diagnostics although poss not when actually idling rough but showed no faults-also no warning lite coming on dash-----------------I know its not 7 talk but is really doing my brain in.Have tried a rover website but guys on there dont seem to know so are ignoring post-anyone work with rovers or had this prob------help please Mike

sounds like aux air valve not opening

Try cleaning out the vaccuum pipes from the manifold to the ecu/sensors. The could be contaminated with fuel/oil/water (delete as appropriate/applicable). Also check all vaccuum conections for integrity.

Hope this helps.

Enjoy

thanks for replying guys.managed to get fault going in drive and with bonnet open did hear a slight "buzzing" from the idle control valve -I wondered if someting in here was sticking and if it is possible to clean although looks like the one I have is a sealed unit -different to earlier models and held on by 4 not 2 screws.this part also emits a high pitched just audible beeping noise on switch off which does go after a short while but i dont know if this is normal or not.
haynes say I need new o ring to change thsi bit so may be worth a look -what do u think,Mike.

right,have spoken to rover specialist today and they reckon idle valve does buzz and makes squeal at swichoff-they suggested more likely to be MAP sensor(manifold pressure)of which they have had some faulty--anyone work with these ??Ideas please -Mike

Have spent another 4 hrs at dealer whilst they tested bits n bobs-they reckon it is oxygen sensor or I would call Lamda sensor-costs £133 + vat-could this affect running after start warm or cold and then clear after 3000 revs-why would it clear at this point-exhaust temp or pressure??-just trying to convince myself they are right before part arrives and is fitted,cheers Mike.

By the time they get to changing the headlining, they will have sorted it!!

It might stop at higher revs because the ecu switches to a different mode or something.
When reading about megasquirt it mentioned something about such things.
Sorry for the vagueness.

lamba will cause rough running when warmed up,wont affect it when cold,you can get uneversal lamba,s for about £40 ish.
try cleaning the aux air valve and make sure it is opening

I took a 3 year old rover 820 to the dealers once.

The brake warning light was coming on.

must be the rear pads I said, not been replaced and ive had 3 or more on the fronts.

nah, they said. bad connection.

take car home, light back on.

bad loom that say, ordering new one.

back for loom. fitted. light come on going home.

takes it back for 4th time. guess what.

plonkers


atb

steve

(For jollys info, it was kingsbury in wellyboro)