Need Help To Diagnose a No Start Issue

[Kassowary]

Hello Bimmerforums!

I've got a 1993 e36 318i with and m42 engine. 177,000 miles approx. and the most recent major project was a replacement of a thermostat, water pump, pump housing, and new belts.

So, on April 13, 2018, I was driving on the freeway, and suddenly my car's engine shut off. There was no sluggishness or sputtering, it just shut off, and generated the curious 1214 code. The tow driver said it may be a vacuum leak. I replaced the spark plugs and checked the wires, to no effect. At this point, the car would crank, and sometimes (after minutes of cranking, or shutting the car off and turning it on again) start, and be drivable for at least a minute or two before cutting out. From there, I pursued an answer in the fuel system. The fuel pumps were checked, heard the noise. Then, I replaced the fuel pump fuse and the fuel relay, to no effect. Then, I replaced the fuel filter, and the car began to start, and immediately die. After one start, the stomp code was 1215, but after a reset, returned to 1214. After awhile of starting it, it came to a point where there it would idle, the die if revved over a certain point.

My next course of action check for vacuum leaks. I found none. Then, I cleaned the MAF and ICV. I did, and now am left with the same issue, where the car would start, then die with the MAF plugged in, and run at an extremely rough idle with it unplugged.

This one has got me stumped. Thanks for the help and please let me know if you need more info.

[shogun]

1214 is not a valid code https://www.bimmerforums.com/forum/s...214-error-code
In case it is P1214 = P1214 BMW - Fuel Pump https://www.autocodes.com/p1214_bmw.html
Did you remove the fuel hose and then test the pump and see if it really pushes the fuel?

Connectd a simple hose to the feed hose of the fuel pump and something to catch the fuel, as shown here on an E32 http://bmwe32.masscom.net/sean750/fu...elDelivery.jpg

[Eric93se]

You have to do a proper fuel pressure test.

[E36328Coupe]

What happens with the MAF disconnected

[ed323i]

You have to do a proper fuel pressure test.

+1

Get a fuel pressure gauge or go to a garage to test the fuel pressure..
If it seems okay, then also double check if the vacuum membrane in the fuel pressure regulator works correctly, by verifying pressure at idle and at load, or two tests at idle, one with vacuum hose connected to fuel pressure regulator and one with fuel pressure not connected. With the M50 and M52 it should be about 2.8 bar at idle (vacuum hose connected) and 3.5 bar at load, or also 3.5 bar with vacuum hose disconnected. M42 is probably the same, but best to look this up in you Bentley manual or on a google search.

If all these tests are good, then you can be quite certain that your fuel pump, fuel filter and fuel pressure regulator are okay (though at high loads the pump or filter could still cause trouble, but not likely)..

[Rooster man]

I concur. Test your fuel pressure. There must be an issue there. Good luck

[Kassowary]

What happens with the MAF disconnected

Rough Idle

[Eric93se]

Replace the MAFS, its very expensive but I found it at Rockauto for a good price, you can check retailmenot for 5% coupon code they usually have. There is a $30 core charge on the MAFS.

https://www.rockauto.com/en/catalog/...ow+sensor,5128

[ed323i]

Technically, it's an AFM (air flow meter), not an MAF (mass air flow meter)..
That's a good price for a remanufactured one..

Does it drive/rev okay with the AFM disconnected? Not sure how advanced the fall-back system is with the older AFM based DME's..