If your "Check Engine" light is on:

GAS CAP ~ Try securing the gas cap first. The "Check Engine" light turns itself off after several start ups,(30?) and then it will come on again if the problem is not solved. From: "Harry Albright" <halbright@comcast.net> Date: May 30, 2006 8:20:02 PM EDT Subject: RE: [z3rides] Check Engine Light/Trouble starting/Low Gas You'll need to read the codes and reset that engine light. It could be almost anything. Reading the codes is the best way to figure out what it thinks is wrong. A loose gas cap can cause it. So can a dirty air filter and many other things.

WATER IN THE AIR PUMP ~ Jeff Armstrong wrote:  My check engine light went on while heading in for an oil change. My mechanic didn't have the part, but said it was a blower fan that started the air flow so you don't smell the exhaust during start-up. I was told it's a 1/2 hour job, but wondered if anyone has experience in replacing the catalytic converter "blower" fan?  Thanks in advance, Jeff '98 Alpine White 2.8 Z3 Holland MI DAN KANE wrote: Jeff, the air pump is located on left side(p-side) in engine compartment along with ecu and 12v + jumper connection..it's black and  makes a whirring noise at start-up (for about 20-30 seconds).It's actually serviceable by the savvy DIY (ie: can be frequently fixed without replacement)..replacement part cost is $275/$234 (oem#11-72-1-432-907) best price at Bell's NJ (bmw-auto-parts.com)...but usually it's the control valve that is the culprit(oem#11-72-1-432-907/$88-$74)..though one should first check the control valve vacuum line as it's often cracked or otherwise leaking (it's non-shielded and very effected by exhaust manifold heat) which causes it to not function, which causes the AP to not function(get it?).. ..the pump is easily taken apart..it's cleanable/restorable (depending) if no parts are rusted through..if regularly serviced (annually)..probably will last life of vehicle..apparently mositure builds up in them and leading to their early demise..if getting a new one..still interesting to break it down..if cleaned up it may even have some value as a "used item. Cheers! dk '97 2.8 bg Jeff Armstrong writes: Hey Dan & anyone else following this thread, Pulled the pump...simple task, and found about 4 oz of water in it, mainly residing in the lower cap at the bottom, where the electrical plugs in. (Weird, because I rarely drive it in the rain...but I'm not the original owner) Cleaned it up and blew out with a air compressor. I wasn't able to pull it apart completely w/o filing off the 6 or so long rivets/grommets sealing up the 2.8's built in 2/98. That may be my next step but I wanted to reinstall the pump to see if I made any progress. It's definitely sucking air, but I think that's the vacuum pressure. At present, I don't believe the pump is working, if so it's really quite. I do appreciate the advice. It may be time to pick up a new part, but it's been interesting pulling it out and attempting to solve. Moral of this story is that if your ECpump begins to make noise, I'd likely attempt to pull it out and see if you have a water issue as well. Any other advice is alway appreciated. -Jeff Holland MI

CRACKS IN THE HOSES (see Cooling System Maintenance) ~Elaina Boyce writes: I had the check engine light come on right after a major service. When we (spousal person and I) looked under the hood with the engine running we could hear a little hiss, and on closer inspection saw that the little hose had a big crack in it. I'm not sure what this hose is, it seems to be a vacuum hose. It certainly had some direct influence over the engine function because when we covered the hole up, the engine sounds changed. There was enough excess hose to cut off the "bad" part and re-attach it. I was pretty angry that this had been "overlooked". Obviously the hoses had not been checked (nor was the battery water level, which led to my car dying on me a month after this "major service". But that's another story). I took the car back to incompetent service person, showed him the pictures of gaping hole in hose. He said that this wouldn't cause the check engine light to come on, but re-set the light and it has not come back on (this was 15K miles ago). Good luck tracking down your mysterious gremlin, Elaina Boyce (and my 1.9 Toadzter Roadzter, Franck)

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