2003 BMW 330ci (Automatic) Crank but no Start

[mikematias]

Well, a little background. Over a year ago I drove to work & parked with about 6 miles til empty. When I get out of work, I walk to my car and try to start it but it would only crank. When I finally got it to start, it sputtered then died out. I tried cranking over & over but nothing(possibly damaging or clogging fuel pump/filter & priming line with buildup of debris). I get gas in the tank & I get the car to start but mis-fires the entire drive home. The following days I have trouble starting car(constant cranking but no start or it just dies out) so decide to replace the fuel pump ONLY & keep the original fuel filter. With the new pump, the issue went away & car started automatically.

The problem went away and everything was fine until about 2-3 weeks ago, I was running Very low on gas but it never died out on me completely from lack of fuel like before.

Now, when I turn the key I SOMETIMES hear the fuel pump shoot, but almost always have to crank a good 10-20 times before I can get any reaction. When my car finally reacts, it doesnt hold idle, it sputters then dies out. After a few more attempts & a few more starts then sputter outs, I can finally get my car to start & stay on. I noticed that this MOSTLY happens in cool weather (nights, mornings) or when I don't drive my car for a couple of hours & seems to ALWAYS happen when its raining. It does happen in hot weather also but MUCH less. I try giving it gas, try starting it on Neutral (which I was told helps start sometimes), but nothing seems to work. It seems to start whenever it feels like it.

All electronics work fine at all times, & oil change is up to date. This started happening out of nowhere, I don't think its the starter or alternator cuz all electronics work fine and engine cranks. I also read something about it possibly being the security system but it has been disabled in my car since I bought it, so I don't think this is even an option.

Im thinking and HOPING, that its the fuel pump again? or maybe the original fuel filter that may be clogged up since it was never replaced when this issue occurred the last time.

If this has happened to anyone PLEASE help me out!

Could it be Spark plugs? I thought about replacing these also but want to rule everything else out first.

[Pelican Parts]

Hello and welcome to the forum! Before spending any more money, pull the car's codes - this will give you a great place to start troubleshooting.

[mikematias]

Does Auto zone have proper equipment for that?

[Pelican Parts]

I would imagine that an auto zone or similar should have a scanner for this around your area; the ones around LA do.

[mikematias]

Okay I will go after work then. I had to leave my car at home for the day because it wouldn't star this morning. Any ideas of what it MAY be?

[Pelican Parts]

Give them a call to make sure that they have something that will work for your BMW.

Okay I will go after work then. I had to leave my car at home for the day because it wouldn't star this morning. Any ideas of what it MAY be?

[mikematias]

Just got home & tried it & it turned on automatically. Seems like the weather does affect how it starts.

[TonyAngel]

I really don't know that problems with the fuel delivery system would trigger a code. It seems to me that the problem always starts manifesting itself when you run really low on gas. Maybe debris in the tank?

If you want to get your car scanned, it would be best to have it done by a shop that does BMWs that have a BMW specific scanner. Getting a scan done with a generic OBD II scanner can lead you on a wild goose chase.

Based on what you described, I'd check the fuel pressure. If you just changed the pump, my GUESS would be the filter.

[MIKYZZ4]

I agree with Tony,
Always replace filter when a new pump is installed, install new filter Now!
Check fuel pressure at fuel rail Schrader valve.
Scan for codes. Post back with results.
Btw, avoid fuel tank levels under 1/4-tank.
Why do I get the feeling this vehicle has been neglected, or periodic maintenance has been ignored?
Let's wait and see what the codes reveal.

[mikematias]

Went to local autozone & got a few codes back
-misfire during start cylinder 1
- 2 for catalyst system effiency below threshold
-2 for secondary air injection system
- coolant thermostat(coolant temp. below regulating temperature)
And finishes by saying "ASE certified Master Technicians have seen this issue on your type of vehicle and the most likely solution is: Replace Ignition coil(s) and Spark plug(s).

But this came from a generic diagnostic scanner.

I was told best bet is to just get a tune up & replace ignition coils & plugs.

But i was also told that sometimes battery problems cause these generic diagnostic scanners to give codes like "faulty catalytic converter," etc.

So not so sure.

[MIKYZZ4]

Clear codes.
Install new filter.
Must check fuel pressure at fuel rail Schrader valve.
Complete a drive cycle, then have a new scan performed.

[Honolulu]

I'd do it in a little different sequence: check the fuel pressure first on a running car. If the fuel pressure is good, the problem is probably not the filter. This saves having to buy and install a filter you may not need.

Only if the pressure is not up to spec, replace the filter and clear the ECU codes. If the car needed a fuel filter, you'll know it then.

Since we don't know any history of the car, there may be other issues. These would be revealed after you resolve the filter matter. I wouldn't replace coils without clear indication that they are faulty. Replace plugs, okay, especially if they look poor when you pull 'em out to have a look.

[mikematias]

& how exactly would i go about checking the fuel pressure? I know of no one in my area with this equipment

[MIKYZZ4]

The same place you had the scan for codes-The local AutoZone!
They will loan out tools for a deposit equal to the purchase price.
This is one example:http://www.autozone.com/loan-a-tools...diagnostic-kit