Rough idle

[Mr_Orange]

Right, still got a rough idle.  No fault codes other than an intermittent 17705.  Also noticing the revs drop down, with lights dimming etc like its gunna stall when coming to a stop (indicates a vacuum leak perhaps?) and a flat spot sometimes when pulling away from a junction etc.

After changing out most of the ignition side of things:
sparks
coil packs
coil pack wiring
MAF
N75
N249

I've decided tomorrow to:
clean and re-adapt the throttle body (again)
fit a new temp sender
look for a possible vacuum leak under the manifold (PCV etc did have crap all over it before I wiped it off recently)

Any handy pointers on the last item on my list?  ie spray some carb cleaner around a bit etc... ? 

[dubcruiser]

I got my thermostat changed at Christmas time and mine runs a lot smoother afterwards. Are you having trouble with the temp guage at all? If your thermostat is faulty then the ECU will cause the fueling to be wrong due to the wrong temp signals. Just a thought and it's not too expensive to change 

[T_J_G]

Already done it!

[dubcruiser]

Already done it!

Ah, must of missed that Tim! 

[Mr_Orange]

Having made myself dizzy researching this I can't help now but think its possibly a vacuum leak issue. 

Can I remove all the crap pipework and perform the PCV/vac pump mod without installing a catch can?....... 

[T_J_G]

Catch can is only about £70...

[Mr_Orange]

Coil pack #4 fitted and no different.  Maybe pulls a bit better now though!

At idle briefly disconnected the MAF and it seemed to idle a bit better.

Will carry on tinkering in the morning again.

[Mr_Orange]

Right-ho:

Coolant temp sensor, done.
Cleaned and re-aligned throttle body.
Cleaned IAT sensor.
Couldn't detect a vac leak under intake manifold, pipes all look a bit manky under there though 
While doing all this I found one of the SAI pipes was no connected properly at the air box.  Must have been like that since I got the clutch done!

Fired it up and it seems to idle a bit better from cold, didn't run it up to temp to see if its better that end yet.  Still seems like its occasionally missing a beat at idle.  Will wait and see what its like warmed up after my drive to work tomorrow.

[Mr_Orange]

Can someone please confirm the part numbers for suction jet pump and crankcase breather valve (puck) on a 2000 AUM?

Thanks 

[radz]

Hi Orange mate

I had the exact same problem if you remember! Have changed my coil as well as you and pretty much done exactly the same as you.

Coil definately improved the driving side and the rough idle but it was still there - turns out my front lambda sensor was completely dead, no voltage coming out at all.

Got that replaced today and oh my what a difference, car seems to be running perfectly!