Unofficialbmw.com

jayray · Joined: 03 Sep 2001 Posts: 6 Location: Jackson, TN

The car: 1997 528i, 68000 miles, regularly maintained

The problem: For the past several mornings starting up the first thing in the morning has not been the normal turn the key and start right up. This morning it would start and immediately die. In fact the only way to keep the engine running was to keep pressure on the gas pedal. I never was able to get the car started so I had to get to work in another auto. By noon, the car finally started, but only with some difficulty. A trip to the mechanic yielded no computer codes, no obvious problems ( isn't that always the case). His suggestion is to do a carbon removal procedure to the valves,

Anyone out there have similar problems? Any Suggestions?

Thanks...

edjack · Joined: 04 Feb 2002 Posts: 3887 Location: San Jose, CA

Sounds like a loose or broken vacuum hose. If a hose fails downstream of the mass air flow meter, the computer can't compensate for it.

Go over the engine and check each hose for leaks and cracks.

Also check all electrical connections for tightness and cleanliness.

sailingphotag · Joined: 11 Jul 2000 Posts: 332 Location: lugoff sc

Hey, i doubt its a carbon thing maybe but i doubt it..i'm not sure how handy you are but my my first move would be to isolate the problem into the "trigoly" [air,fuel,spark]fortunatily almost anyone can isolate that far.AIR you got unless you are on the moon...FUEL get a can of quick start and a fire extengusser and an assitant, giver a shot [do not keep sprayin and sprayin 2 seconds max for this ] with moter turnin over spray into air filter box [take filter out] if she starts its fuel related....if it dont its spark related or moter is broke {stuck valves broken head ya know] pull a wire off and hold near ground 1/4 inch gap or so spin moter you should see a fat blue spark....let us know ...jeff

charliesmith · Joined: 07 Jul 2001 Posts: 738 Location: Dallas, Texas

Jay,

It would be nice to know what the vacuum reading is in the intake manifold at idle. Plug a vacuum gauge in. Anything less than 15 hg. is definitely an intake leak. Find it and problem is solved. The big rubber intake elbow between the mass airflow sensor/air filter and the intake manifold on my '84 528e got hard and tore/sheared at the convoluted flex rings allowing heaps of unmetered air volume into the induction system. The engine barely started and ran on the very lean air/fuel ratio. It was difficult to detect. Check yours. Your problem developed suddenly. It will be fixed as fast. Pass on the carbon scam and run away from that mechanic. I really question his integrity and grasp of things mechanical.

jayray · Joined: 03 Sep 2001 Posts: 6 Location: Jackson, TN

Thanks all for your input and help. I did pass on the valve cleaning job and will look for a vacuum leak. Funny thing though is that this is a rather sporadic problem. The past few days I have had no problem whatsoever starting in morning or running up and down the highway. I will mention though that a few months back, I had a similar problem starting problem followed by what I can only describe as a Hiccup when running ( loss of power) which caused the check engine light to come on. It set a computer code that the dealer said was the crank sensor. I was prepared to pay $$$ for repair (out of warranty) but they generously fixed it for free, which made me wonder if it was just a loose wire or something simple.

In defense of the mechanic, I do believe that he is both honest and a good man. He looked for a vacuum problem, checked computer codes and a bunch of other things. He also related to me a past experience with a BMW, where the owner replaced a bunch of electrical parts, but the problem turned out to be the carbon thing. But I think that starting problem was an everyday thing, not sporadic like my case. BTW he spent some time going over my car and charged me $0, for the good will, which I thought was more than generous.

charliesmith · Joined: 07 Jul 2001 Posts: 738 Location: Dallas, Texas

Jay,

Kudos for backing your wrench. I misjudged him. I hope he doesn't browse this site.

sailingphotag · Joined: 11 Jul 2000 Posts: 332 Location: lugoff sc

Hey, anotherthing my '82 528e at times does what you discribe starter spins and spins and car will almost start then finally will and is fine the rest of the day...always passed it off as intermittant check valve in fuel pump,alowing the fuel pressure to bleed down and starter has to run awhile {well actually fuel pump}till it gets enough to start ive never t'shot the problem though just listen to the kids dis Henery [the cars name] so i'll be interested to know what your mech finds...jeff