Hi all, after selling my E38 7 series 6-7 months ago, i'm back in a beamer an S reg 323i with a 2.5 engine (confused, can anyone explain?)

Really pleased with it overall, drives really well and the engine pulls like it should but is a little lumpy/rough on tickover, doesn't stall just hunts a little, from what i've heard it could be the idle control valve but can anyone tell me if it maybe something else?

Any help appreciated, cheers in advance

Anyway here are a couple of pics

Welcome aboard matey...

Its a straight-six 2.5 M52 unit with a manifold restriction to earn its 523 badge !!

Welcome aboard matey...

Its a straight-six 2.5 M52 unit with a manifold restriction to earn its 523 badge !!

Can this restriction be removed Dabsy? And can you tell me why bmw done this?

RHD/LHD models were built to stock spec regardless (unless you purchased an "Individual"). Colour, running-gear, engines and interior were chosen at purchase... Looms, chassis and engines are stock from production line.

The straight-six came in 3 guises (4 upto 2002) - Their badge ! The restrictions were obtained in their manifolds, Throttle-bodies and ECU/DMA's (and obviously their corresponding sensors).

Straight-six config - 520, 523, 525, 528

Righto got ya, so ther than tge manifold the engine in my old E38 728i is the same as my E36 323i, could i put a 2.8 or a 2.5 manifold on my 323 then?

Can anyone advise on my idleing issue?

Any help would be greatly appreciated

Rough idling is a direct result from either - erratic fuel pressure, failing crank/cam sensor(s), fouled up MAF/Throttle Body/Intake hoses or poor engine breathing... Oh and of course, engine timing/hi-tension electricals inc. plugs, leads etc.

Start with the basics and thoroughly clean the intake system (All of it) ;)

Thanks Dabsy, will try cleaning all the intake system at the weekend, your help is much appreciated, so do you think that uprating the intake manifold is possible then?

So i cleaned all of the the intake system over the weekend with no joy, i have taken the spark plugs out and they look like they could do with replacing so i am going to replace them and see if this makes a difference

So can anyone advise me on uprated manifold options?

Any help greatly appreciated