being there in drive but not in park or nuetral would indicate its a transmission problem. (im not a mechanic i could be wrong)

have you tried to reset your ECU?

i had rough idle caused by a dodgy coolant temp sensor. but the rough idle went away when the car warmed up and was not affected but being in gear or not, also mine is manual.

to reset your ECU unplug the battery +ve over night (says one hour but just to be safe) and then plug it back up in the morning. start the car and let it run without touching a thing for 15minutes atleast. ie dont put it in or out of gear, dont touch the accelerator, just let it run itself.

I'll give resetting the ecu a try.  It would be nice if it proved that easy.

I have considered a transmission problem but don't really know enough about them to narrow it down at all from there.



I

Yep.  Checked for fault codes but thre weren't any.

LE7SGO;168019 wrote:

ive also had similar probs in my rx (manual) but mine occours every now and then when stopped at the lights or something it will drop to say around 250 rpm and feel like it almost stalling with its shakes and what not.

would be interested to see if anyone can shed some light on this matter.

if it goes away when the car is warmed up then it's a problem with the coolant temp sensor... i have this exact problem, but i'm just ignoring it, seen as i'm replacing the engine soon...

if the car always does it then i'd suggest adjusting your idle so it sitting a bit higher... 800rpm is the norm i believe

Thanks guys. The idle is a little rough normally but can shake quire seriously with the aircon on.  It does not go away when the engine is warm.  In fact, the amount of roughness is pretty well the same whether the engine is warm or cold.  Only having the aircon on aggravates it.

I have ruled out the engine mounts and vacuum hoses.  That's why I was leaning towards the fuel injectors.  Of course, there could be multiple causes.

It seems that others have the same or similar problem to me and are prepared to live with it.  I don't want to give up on it yet!

Hey bud, juding from what you have said I would say you have a dirty or u/s air idle speed control motor. This would account for your rough idle (loss of rpm) in drive gears & especially when the a/c is on. The AISC should also bump up the rpm when you turn the steering or any load is put on the engine, eg thermo fans etc. Over time the valve can become blocked with carbon resulting in poor function, remove valve & clean with carbie clean then lube with crc or similar. If still no good the valve may be stuffed & need replacing. See it fairly often on EFI cars at work, hope this helps. Regards Jon