2001 525 fuel injection question

One morning last month the car would not start. It cranked but would not turn over.

The dealer said the engine was flooded and had to be cleared. Here's the thing that has us puzzled:

He said, if you back out of your driveway just a few feet and turn off the engine, then turn it on again and travel a few feet back into the garage, then turn off the engine, it will flood it, and no amount of time and re-trying will get it to start again.

Sure enough, we had backed the car out just a few feet the day before, washed the car in the driveway, and had returned it to the garage afterwards.

The mechanic said, to avoid this happening again, to travel around the block once before returning the car to the garage. He said he frequently sees this with the fuel injected engine.

My husband says this is crazy- he has never heard of such a thing.

Has anyone had a similar experience or know anything about this?

Thanks. PoohBear

Reply to
poohbear
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I've certainly noticed this with my 528. It lives on the street, and one morning after a cold start I realised I'd forgotten my phone and went back indoors for it - obviously stopping the car for my house keys. On re-starting, it was unhappy and missed slightly until it warmed up when all was well again. Dunno about trying this twice ;-)

However, like any flooded engine, I'd try flooring the throttle with the ignition off, and then keeping it there while trying to start. Works with most.

Reply to
Dave Plowman (News)

I have had the same thing happen to a variety of fuel injected cars. They will always start, though. It just takes a while of cranking. (BTW, this only happens about 1 every 50 car- backing- into- the

-driveway- events.

Reply to
Tom Wright

Thanks for the info, Tom.

PoohBear

Reply to
poohbear

The next morning and afternoon it still would not start. The tow guy tried also. Finally, it had to be towed....the BMW dealer said the lines were completely filled.....

Thanks for the info.

Reply to
poohbear

I had it happen with my 525i. Normally it starts with no trouble at all. Started it one evening. Ran it for about 2 mins, and switched off. Next morning, it wouldn't start. Floored the throttle, and it nearly flattened the battery, before it started. Mike.

Reply to
Mike G

It's actually a very common affliction of almost any modern fuel injected car. What happens is the ECU sees the low temperature from the temp sesnor and enriches the mixture for easy cold starting by opening the injectors a lot. If you don't run the engine long enough to fully burn this off or warm up the engine when you continue to stop and restart the cold engine it keeps dumping more fuel into the intake. When the mixture is too rich (there is too much fuel to the amount of air) it will not ignite. This is the "flooded" condition.

You can either just leave the car to rest and the fuel will dissipate or you can try cranking the engine with the throttle plate wide open. The problem with the latter is the ECU will see the WO throttle and attempt to dump even larger amounts of fuel in to match the incoming air.

Some folks who run into this fairly often learn which fuse goes to the fuel pump and will pull that and crank the engine with WOT for a while in an attempt to clear the flooding. That may not work as the pressure on the fuel rail is pretty high, holds for a long time and would probably be able to deliver quite a lot more fuel from the static pressure alone.

The easiest solution is *don't* flood the engine in the first place. Once you start the car, try to always let it run for long enough for the temp gauge to at least budge off the left rest before shutting it down. Sometimes, it cannot be avoided for safety sake, etc. Certainly, don't short cycle the engine (start-stop) more than once consecutively.

-Fred W

PS - BMWs don't do this nearly as much or as severely as my old 88 Mazda RX7 used to. The rotary engines were notorious for flooding if you ever start them and turn them off before reaching operating temperature.

Reply to
Malt_Hound

The "lines"? What lines? That does not make the least bit of sense. How much did they charge you for clearing these lines?

-Fred W

Reply to
Malt_Hound

Wonder if there's an easy way to disconnect the feedback to the ECU from the coils? Usually if no spark is registered the injectors will be disabled.

Reply to
Dave Plowman (News)

Bullshit.

I take my car out of the garage and put it in the driveway, then put it back in the garage, then drive it.

And, you can clear the fuel from the motor by holding the gas pedal to the floor. Do not pump it, hold it wide open. More air than gas will be delivered, and it should clear it out. It if sputters and tries to fire, then release the gas so the starting sequence will revert to normal. You should not have to press the gas to start any fuel injected engine, but once the engine has been flooded, holding the throttle wide open is the recovery mode.

I agree with your husband.

Reply to
Jeff Strickland

I thought that is what he told me via ph Customer states vehicle will not start. Inspection showed vehicle very difficult to start, very long cranking time. Inspection showed unspent fuel in cylindres. Clear intake and cylinders.

(charge- $46.06)

Thanks for everyone's responses!

PoohBear

Reply to
poohbear

OUCH!

You just paid $46.06 to hold the gas pedal down while turning the ignition switch. I can't help but wonder what, if any, parts they used to justify charging $0.06 in sales tax.

Reply to
Jeff Strickland

OUCH!

The Tow guy did exactly as you describe before he towed the car. It would not start after waiting a day in the garage.

Thanks for the info.

Reply to
poohbear

I'm not conding their actions, especially without more information. But diagnostic work has to be factored in. Otherwise is like claiming that a doctor charged you $100 just to write a prescritpion, and not include the work to arrive at determining what to prescribe.

Reply to
Ignasi Palou-Rivera

Sorry to harp on this, but I'm gonna.

I had never had this happen to me, ever. Then, on Sunday it happened with my motorhome, and I was trying to sell it. The buyer asked if he could start it, I tossed him the keys, and it cranked and cranked but refused to start. It had never done that before, I often will start it by simply reaching in the window and give the key a quick twist. It never cranks even a full rotation before it starts, but Sunday when a buyer was looking at it, it cranked and cranked, and cranked some more. I looked at some stuff and tried to get a fuse out, but couldn't. I tried again and it started right up. I was thinking I would need the tow truck to get it home, but it turns out that I was having exactly the same trouble as you guys had. I had a previous looker about an hour earlier and he wanted to turn the generator on, but the gas tank was approaching E and there wasn't enough gas for the generator. I took the vehicle over to the gas pump, 50 yards away, and put in $50 so it wouldn't be E if somebody wanted to go on a test drive or take it to a mechanic. After getting the 50 bucks of gas, I drove it 50 yards back to the spot where it was. Of course, I started and stopped the motor at the beginning and end of each leg of the 50 yard trip. About an hour later, a second looker wanted to hear the engine run, and this is when it refused to start.

What happens on short runs like that is the plugs get very wet, dripping wet, with fuel, and the plugs don't spark well when they are that wet. There are two ways to dry them, pass lots of air over them, or wait for the gas to evaporate. One method takes several attempts at starting and might seem like endless cranking, the other method takes a very long wait.

Granted, my motorhome and your BMW share very little other than they have engines and tires. But the engines in both are fuel injected, albeit the BMW is a vastly superior system, and the fact is that I used my motorhome in pretty much the same manner as you used your car before it decided to not be your friend anymore - we both drove very short distances that involved two or more starts very close together with extremely short run-times. I would not have thought that the short trips were the cause of my troubles, and when you related your story it took me three days to think about what you went through and how it is nearly identical to what I experienced.

The good news is, there is nothing wrong with your car and you don't need to worry about it. The bad news is, you paid somebody to turn the key a bit longer than you attempted to turn it, and you lost a day waiting to get your car back.

Reply to
Jeff Strickland

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