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Topic Review (Newest First)

  • 10-02-2009, 05:56 PM

    Indeed... however, easier to check everything

    which easy and as simple as the ICV... on those E38 prior to 1998 production date...

    "Keep Right, Pass Left. It's the Law."

  • 10-01-2009, 02:52 PM

    Rough idle possibilities

    Vacuum leaks always cause rough idles. Verify it's not that before you spend much on ICV's etc. My indy shop friend used a 'smoke machine' to confirm my vac leak. It pumps smoke through one of your vacuum hoses into the induction system and indicates leaks. I think you could make one with a small piece of of pipe. Put an end cap on with a hole big enough to hold a cigarette filter. Put a lit cigarette in the hole, insert it into the pipe. Blow into the other end and it should make plenty of smoke. "Smoking Shops" sell similar gadgets for stoners. Hold the end cap to a disconnected vacuum hose. Stuff the air filter inlet if necessary. Those wide red Profile Gaskets on either end of intake manifold are only partly compressed. When they dry out they shrink and leave big gaps.
  • 09-30-2009, 12:06 AM


    Thanks again for the areas to check on my car. I would like to tackle some of these myself to save money. Could u please email the links to me when u have time. zolmax at hotmail dot com

    Also if u could tell me the easier fixes to try first or the most likely cause it mite be.

  • 09-29-2009, 08:40 AM

    Re: Rough idle problems

    Mate... perhaps a bit of witchetty grub may work. However, as per previous discussions regards car problems... replacing MAF was not the solution or as to whether part numbers match or not in spite of your car being a 1995 730iL... similarities with other E38 exist whether built for the Americas, Europe, Asia or Australia. Make sure the plugged to the MAF fits correctly. Other problems could ICV or idle control valve, vacuum problems, spark plugs, CPS failure or even a dirty air filter or the air duct is clogged debris. Also check the CPS is known as the cam position sensor [sit on the right of the upper timing case], and the crankshaft position sensor sits next to main pulley and water pump… check either and cleaned… as well as the ICV… which could be dirty or clogged with dirt, and try using an electric cleaner if possible [brake cleaner spray also works but it is a bid to strong]. If you need diagrams you know where to find them or email me for URL...

    Regards from Austin, Texas

    "Keep Right, Pass Left. It's the Law."

  • 09-27-2009, 08:29 PM

    Rough idle problems

    While waiting at traffic lights the car will idle as normal then suddenly it just seems like something cuts out and it starts to idle really rough. It has slight hesitation on accelaration but pnce rolling it drives normal untill i stop at the next lights and it just idles rough as soon as i stop. Also when it idles rough like this and i do slow turning for example parking, i hear some sort of squeel and the steering seems like it slipping but when the car is idleing as normal this does not happen and all is perfect. If i do a lot of driving the problems seems to go away.

    I have installed a new bosch maf.

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