So on Saturday my 2000 740il wouldn't start. The starter engaged and ran on. After 6 or so attempts it started and ran fine (no SES light). This morning after Starbucks, driving at 30mph it dies, no sputer or anything just dead.

Whithout a SES light on I asume there are no codes to read, correct? I have a Peak tool to do just that. It would appear to me to be fuel or spark, probably fuel delivery. Any thoughts on where and how to start looking at this?

Any help would be much appreciated!!!!

Sounds like the infamous Cam Positioning Sensor (CPS) to me!!!:buttrock

With a CPS issue the SES would not come on?

Check your battery connections, first.

Make sure they are tight....

After the car died on you, did you have any electricals at all, eg: Check control, seat belt warning, BMW Assist Inactive etc?

Normally, cam position sensors will trigger the SES light...not sure if the crankshaft position sensor would though.

jake

Yes, all electrical intact. The starter engages and turns just fine.

Yes, all electrical intact. The starter engages and turns just fine.

Check the thermostat wiring at the thermostat. The connection can leak and wreak havoc.

Sorry to hear that Dawg.... hope it all works out

Check the thermostat wiring at the thermostat. The connection can leak and wreak havoc.

This fixed my problem. I had the same symptoms...

If the car thinks it has already warmed up, you will get a lean mixture and the car will not want to start. If the car is already warmed up, you would get the reverse: Too much gas and not enough air and not want to start. I had an Oldsmobile once which did that...the engine temp sensor went bad....mixture was too lean to start.

Proceed from the simple to the complex.

jake

Replaced the fuel pump and fuel filter. Car starts. Half way down the drivway car dies. Three minutes later alls good. Drive to the office, head home an hour later all good so far. An hour later no start. Wires near t-stat look fine. Still no SES light

Any ideas?

do you know a good BMW indy in your area? Might be good time time to pay him a visit, not good for you to be stranded somewhere when the car croaks again.

That sounds like the CPS. Mine did not throw the SES light immediately but after awhile it came on. My car would die and then after letting it sit for 20 min it would start up but try to die. I would have to accelerate just to keep it alive at a stop light.

In my experience, if a car just dies, but will run if you force it by judicious use of the accelerator, wants to die at stop lights, etc.....

....the problem is the MAF, (especially the on the BMW (e30), and also the Nissan (Altima) which my son owned).

Try replacing your MAF, not the entire housing, but only the element, from a Rover. Do a search on Google, or some of the other sites like Bimmerfest, or Roadfly,and find out which Rover unit is compatible (costs something like $105). Some of the Rover units are direct swaps, but cost much less than BMW. Some folks even say VW units are compatible, but the majority tend toward Rover.

I have no idea why your SES light is not illuminating...usually it will.

If one had a standard transmission, one could keep the RPMS up (once it starts) until the car warms up, and then, most times it will keep running. Once the engine is shut down, however, one would have to work the throttle to get it up and running once again.

jake

Thanks all. I replaced the MAF a couple of months ago to clear the SES. I am going with the CPS, should have listened to TxDarth. My only question is which to purchase. Autohaus AZ lists a Camshaft Position Sensor and a Camshaft Position/Reference Mark Sensor. My guess is to purchase two of the later.

Any idea?

Your car has 2 CPS sensors so you should replace both. Here is a link that may help you
http://www.bimmerboard.com/forums/posts/77352

Ok, replaced both CPS, car started ran and died. What am I missing here?

Any thoughts?

Okay, had it towed to an indy shop. They come up with the DME being bad. Can I purchase a programed DME anywhere? They tell me I need to go to the dealer.