PDA

View Full Version : Help - 525 won't start



mjfeeney4
09-02-2006, 10:18 AM
After sitting at the Philadelphia airport my 1995 525i turned over fine but did not start ( 1AM in the morning and tropical storm).

The car has previously shown no signs of problems but the symtoms are similar to a bad fuel pump replaced about 2 yrs ago.

1. Even though the battery seemed strong and the engine turned over normally, could a low voltage ( aging battery) cause the engine not to start?

2. Rains have been heavy but the engine compartment appeared dry. Could moisture cause an electical problem?

3. Posts mention checking fuel pressure and flow, but few details on how to perform the test. Should I just disconnect the fuel line at the fuel injector rail and turn the ignition switch to #1 position, check for flow? OK, so I checked the Bently and will test the power to the fuel pump connector and fuel pressure/flow.[/B]

4. Could check the fuel pump for voltage (bad relay or fuse). Might buy a fuel pump to bring with me and try a replacement in the parking lot (I hate the smell of gasoline in the morning).

Any suggestions would be greatly appreciated. Not the best day to be troubleshooting ( rain and wind) at the airport parking lot.

mjfeeney4
09-02-2006, 05:22 PM
Began troubleshooting today, here's what happened:
1. Checking fuel pump, power, pressure both OK.
2. Tried a stomp test to see if there were DME or ECM faults
3. Could not get the pulses/code to begin so tried several times ( 5 stomps in 5 seconds, tried maybe 6 times but no code))
4. Smelled gas and sure enough, there was gas pouring out of the air filter area. Removed the air filter cover and liquid gas was leaking out of the air intake. Must have leaked 100 to 200 ml of fuel before it stopped. I guess the fuel pump must be delivering enough pressure.

Has anyone ever heard of this or experienced this problem. I find it hard to believe that the fuel injectors would deliver that much fuel in only 2-3 minutes of trying the stomp test.

Looks like the tow truck is going to have to take her to the shop ( I hate paying an independent to fix my car).

BillionPa
09-02-2006, 10:41 PM
if an injector stuck open that could happen.

mjfeeney4
09-03-2006, 08:24 AM
It is strange that there has been no indication of starting problems prior to today. The engine had always started in 1-2 seconds, so I could tell right away something was up. The engine did not fire on any cylinder, after trying several minutes of turning over. Disconnecting the battery to reset the computer had no effect.

Been reading many past posts and the list of items now includes: Main relay, crank position sensor (CPS), DME, and mass flow sensor. The posts recommended checking for spark but I am not sure how to do this with the M50 with the coils over each plug. Do not have a scope and the car is still at the parking lot at the airport instead of in my garage where all of this would be much easier.

BillionPa
09-03-2006, 10:35 PM
MAF wouldnt do it, as the air shouldnt be metered while cranking. the main relay will die suddenly, and if you have never replaced the DME and fuel pump relays, do it anyway. that will narrow down the problem some and get rid of a maintainence item.

the leaking fuel though is a BIG problem and should be addressed before trying to crank again.

mjfeeney4
09-06-2006, 06:35 PM
The reason for non-start was water backed up into the computer compartment. There was so much rain and wind, that the drain under the hood near the computer compartment plugged, allowing water to enter the drain at the bottom of the computer compartment, filling it almost completely with water. The main relay, fuel pump relay, transmission computer and ECM board were sitting in water.

This explains the failure to stomp test, and the fuel injectors dumping gas continuously into the intake ( when the key was turned to position 1 or 2).

I hate tropical storms. :(

Ross
09-06-2006, 06:55 PM
Open them up and dry them out before things corrode. spray any crud out with contact cleaner. Worked on a cell phone that went swimming!
This sounds like a casualty to me. Your insurance may cover.