M50 engine doesn't start, NEED HELP

[Qsilver7]

...I need to move the car and I don't know how to get the transmission lever into neutral. Martin
insert key into ignition and turn to position 2
place foot on brake - press down & hold while you,
place hand on gear select lever and move it back to N

Also, not sure why you would press on the accelerator pedal when the car has direct fuel injection?

[BMWCCA1]

I'm a bit confused by the order of posts within a thread being sorted improperly lately but I think the question was about not starting. I'll let you sort out the neutral thing when you've not had a drink in a while! ;)

M50 engines are famous for "flooding" when started and run a short time, like when moving the car for washing, etc. The plugs get soaked and then if it does start, they get sooted immediately. The best thing to do the first time this happens is to floor the gas pedal and start it then drive the car for a long time. Otherwise you'll probably need to remove the plugs and either clean or replace them. Sometimes just a blast with carb cleaner and blowing them dry with compressed air will do it, other times a bead-blasting plug-cleaner may be necessary. This seems to happen more with the correct plugs being used and less with the ubiquitous $2 Autolites many have used with great success.

Did you maybe last move the car just a short distance?

[werminghausen]

I wanted to start the car but it didn't fire up as usual.
I did press the gas pedal a bit and it fired but in a very odd way. The engine died at once when I wanted to get back to idle. I tried again and started with the foot on the pedal. the engine misfires, smokes and stinks and dies immediately. I need to move the car and I don't know how to get the transmission lever into neutral. Martin

[Russell]

Remove plugs, clean or replace them flooding after just moving the car. That realy seems extreme!! Mine will always start run rough for a few seconds in this situation then smooth out. IMO, something major is wrong if this happens on some M50s.

BTW, I change my plugs every 30,000 miles. last time I replace the coil to plug boots and changed the valve cover gasket to help ensure minimal oil in the plug tubes. The car in question may have some basic ignition issues.

[werminghausen]

Did you maybe last move the car just a short distance?[/QUOTE]


Forgive me. I figured out the release of the lever.
With the foot on the accelerator pedal the brake is difficult to get to.

Yes it is true. I moved car only a few feet in order to change tires for winter.
I tried to start the car again and move but this seems to be almost impossible.
same thing. It starts for second and then shuts off. With the accelerator half down it would not die but fire oddly and misfire. I can hear the explosion in the muffler and I see lots of white smoke.

Would you think I should try to get the car on the road and drive?

[werminghausen]

I took out the plugs and they look dark/black. I installed them back and tried to start but I have the same issues.
I will take them out again and replace. Then I'll try again and report back.

[Russell]

Vacuum leak sound like a good possiblity.

[werminghausen]

Remove plugs, clean or replace them flooding after just moving the car. That realy seems extreme!! Mine will always start run rough for a few seconds in this situation then smooth out. IMO, something major is wrong if this happens on some M50s.

BTW, I change my plugs every 30,000 miles. last time I replace the coil to plug boots and changed the valve cover gasket to help ensure minimal oil in the plug tubes. The car in question may have some basic ignition issues.


Russell
I took out the plugs, took out fuse 23, fuel pump and let the engine turn.
Then I put new plugs back.
Same issue, nothing changed. Engine would start for a second, then die unless I push the pedal, misfiring and white smoke.
It was probably silly but I started the engine and went for a 1/2 mile test drive because I thought probably the car might come back to normal. But it didn't.
The engine was weird. It had no power, I had to be above 3000rpm and what amazed me was that there was no brake power, as if the brake booster didn't work, also the transmission didn't work as usual, no shifting, the check engine light went on.
Thank god I managed to bring the car back somehow. This was not easy. At my driveway there was white smoke coming out of the tail pipe probably 2 minutes as if water would be boiling in the muffler.

Any idea what the problem might be? Martin

[bubba966]

Sounds like you've got a vacuum leak.

Check the intake boot (between the air filter assembly and the throttle body).

Check the O-Ring on the vac line fitting at the front of the valve cover.

Check that the fitting for the large vac line from the ICV to the intake manifold is in one piece and properly inserted into the manifold.

I had a problem like this on a '95 525iT and the code kept coming up as a bad MAF. Swapped MAF's, no real change. Got a new MAF, still was doing it. Replaced the intake boot, no difference.

Finally found that the plastic connector from the ICV-Intake vac line had broke the retaining clip off, and the vac line had worked itself out of the intake manifold. Got a new connector at the dealer and it ran perfect after that.

You can check this connector w/out taking the manifold off. Just pull off the throttle body (throttle bodies if you have ASC) and look into the intake manifold. You should see this connector right at the base of where the throttle body bolts to the maifold. If it's fallen out, or is easily pushed out the retaining clip has broke off and you need a new connector.

[werminghausen]

After yours and Russell's comments I checked the manifold for leaks.
Guess what I found the Manifold- ICV connector loose. The plastic arm that holds the connector in place must have been broken and the connector slipped out. So this is clearly the cause for having no break boost and weird transmission. I hope the engine is doing fine now as soon as this hole is closed.
Will this test drive yesterday have any negative impact on the computer. Do I need to reset something?

[werminghausen]

Forgive me for my stupid question about the lever.
Main thing was that the huge vacuum leak caused by loosing the ICP connector in the manifold. This must have caused all the trouble- no flooding I think.
I'll try to attack this connetor. Martin

[Ross]

Correct the vac leak and all should be well. If anything the O2 sensor might have told the computer of the wrong mixture but if no light then no worry.
Resetting the computer ala Shogun reset will certainly get things back in order.

[bubba966]

After yours and Russell's comments I checked the manifold for leaks.
Guess what I found the Manifold- ICV connector loose. The plastic arm that holds the connector in place must have been broken and the connector slipped out. So this is clearly the cause for having no break boost and weird transmission. I hope the engine is doing fine now as soon as this hole is closed.
Will this test drive yesterday have any negative impact on the computer. Do I need to reset something?


That damn connector was exactly what was giving me trouble for a few weeks. At least you figured it out sooner than I did, though I didn't have anyone to tell me to check that.

Replace that connector and all should be fine. Though you might want to disconnect the battery and leave it disconnected for an hour or two to fully erase any codes the computer has in it. But if you've got a code reset tool just use that after you replace that connector.

[Russell]

I suspect it was unburnt fuel in the exhaust system due to a lean misfire.

[Russell]

shogun reset will at least reset your trany computer. I did it a couple of years ago. It made the trany shift different for a few days, then it seemed back to normal for my type of driving. Not at all sure about any other computers such as the ecu resetting.

[werminghausen]

I removed the throttles and kind of fixed this connector: the clip was broken. I managed somehow to drill a hole into the plastic connector fin at the broken clip, then I secured the connector with a binder/ cable clip. The engine was starting as if nothing happened. All is fine again, no memory of the nightmare left except the check engine sign.
I tried the shogun reset but was too tired to test drive. I assume all is fine now.
However I will exchange this connector as soon as temperatures are warmer.

I read messages about the shogun reset that once the computer is reset the 'car brain' is learning and adjusts itself to the driver? Sounds too god to be true. What is your opinion?

[werminghausen]

Thanks bubba966
your note was it. It was the vacuum leak. I have the car back and I am so happy. It was this stupid connector. I was lucky in the end that this happened in my yard and not 500 miles away.
There seem to be not that much people experiencing this. May be we two are very unique, but this culprit should be on some list of things that could happen with an old bimmer with a brittle connector. The thing is that the location is so not visible.

[werminghausen]

Russell
what I wanted to ask: what was the intense white smoke during my test drive with the vacuum leak. When I stopped the engine white smoke was coming out of the tail pipes for about 2 minutes. It made some sound as if water was boiling. Could it be that water is in the muffler and the muffler got extremely hot through the explosions in the muffler (I told that I thought I would hear explosions in the exhaust?) What do you think? Martin

[bubba966]

Thanks bubba966
your note was it. It was the vacuum leak. I have the car back and I am so happy. It was this stupid connector. I was lucky in the end that this happened in my yard and not 500 miles away.
There seem to be not that much people experiencing this. May be we two are very unique, but this culprit should be on some list of things that could happen with an old bimmer with a brittle connector. The thing is that the location is so not visible.

It must not be too unique of a problem as the local dealer had that part in stock. But I've not heard much anyone else say they've had that same problem...

[Morgenster]

It must not be too unique of a problem as the local dealer had that part in stock. But I've not heard much anyone else say they've had that same problem...

It's definitely not unique cause I've had that elbow pipe pop off at least four times with LPG backfires. My mechanic told me that he systematically fastens the thing down like the OP did with a piece of steel wire on most of these engines.