what rpm does your 540ia idle at?

[markus]

mine seems really low. almost at like 500rpms. sometimes a hair under. it also is sometimes kinda rough. my guess is I have to rseal my intake manifold front and back, and underneath.

[winfred]

m60/62s run 550-800 depending on what's pissing them off and what mood they are in, they are usually happy in the upper 600s low 700s, the intake leak will screw with it pretty good

[markus]

thats what im thinking. sometimes it will "chug" and barely stay at 500rpms and acts like it wants to stall but doesnt.

[dt8068]

mine idles at 500, sometimes at 490, although I'm pretty sure it's not supposed to be that low. Idles at 600 with a/c on.

[BillionPa]

mine is at 480 when warm after idle, it idles smooth and has no hesitation when i put the pedal down.

when its cold (like, 0F) it starts at 900, then drops to 750ish in about 20s, then will continue to drop as the engine temp goes up.

[Boom n Zoom]

m60/62s run 550-800 depending on what's pissing them off and what mood they are in, they are usually happy in the upper 600s low 700s, the intake leak will screw with it pretty good


That's some funny **** winfred

:D

Mine has just started running very similar to that and the best part is it's after I have replaced the Ducting between the MAF and the Throttle body. I guess it may have now begun to leak.

Will do a bit of a search and run some checks.

Cheers!

[pingu]

Mine generally idles at about 600 rpm. O think the specification is 600 +/- 50.

Mine used to generally idle at 500 - this idle speed would sometimes couple to the chassis (maybe the motor mounts are due for replacement) but I wouldn't say it was rough.

I had the PCV plate changed which made a slight improvement. I then had the valve cover gaskets changed and now it only occasionally idles at 500.

[mattyb]

just under 500 with no hesitation or issues. does sound a bit lumpy sometimes but sounds goooooooooood!

[Barney Paull-Edwards]

just under 500 with no hesitation or issues. does sound a bit lumpy sometimes but sounds goooooooooood!
Easy test for your BMW Manifold leaks. Buy a can of "Easy Start"(or what ever they call it over there,carbon tetrachloride), warm engine, spray carefully on manifold,when revs go up you have found the leak, if they do not, no leak.DO NOT try this with a diesel, it will not work due to no vacuum,teaching granny to suck eggs i know but its amazing how many people break top rings in diesels with "Easy Start".

[pingu]

I haven't got a diesel but I'm just curious as to why you can't use Easy Start to find a leak on a diesel. I thought that as the pistons in a diesel engine descend, they create low pressure in the cylinders which sucks in air (via the air filer and manifold etc). So why is there "no vacuum" in a diesel?

[winfred]

theres no throttle plate on most diesels for the pistons to suck against, they allways draw a full air charge and fuel quanity is the limiting factor on engine speed, where a gasser wants to be around 14-1 air/fuel ratio a diesel is happy with 50-1 or so at idle and maybe 20 to 30-1 under load


I haven't got a diesel but I'm just curious as to why you can't use Easy Start to find a leak on a diesel. I thought that as the pistons in a diesel engine descend, they create low pressure in the cylinders which sucks in air (via the air filer and manifold etc). So why is there "no vacuum" in a diesel?