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Not a good day!

1K views 17 replies 10 participants last post by  Formula 1 
#1 · (Edited)
So here's my day. Ill try to explain everything as well as I can.

I pulled out of my driveway today to go to work which is about 2 miles away. The OBC says I have about 50 estimated miles left on the tank. No problem. I'll get gas at my usual Shell after work which is about 4 miles from work. Halfway to work, my fuel light goes on. Again, no problem, I'll get gas after work. I park and walk into work.

I walk out of work and turn on my car. Somehow, now I only have 40 miles left on the computer. I realize I probably should not have let it get this low. So I pull into the gas station with no problems. At this point I've only driven with the light on for about 4 miles. I fill up, start my car, the car dies. I wait a few minutes, the car starts fine, and I am on my merry way. On the way home, my car starts chugging under acceleration! After a few miles, It is back to 100% normal. No more problems, or so I thought!

This next part isn't really relevant to the car per se, but it could have potentially been the icing on the cake. My car is an outdoor car. It sits outside all the time, and the national weather service alert on my phone says SEVERE THUNDERSTORM WARNING! QUARTER SIZED HAIL! So now I am freaking out that on top of whatever damage exists inside my car, there will now be huge dents in it too. So I went outside and parked my car under a tree and put some cushy blankets on it to soften the blow of any hail.

Luckily, no hail occurred. Just a monsoon and some pretty cool looking lightning. Crisis averted. :thumbup:

So I then I go back outside and take my car for a little test drive. Under acceleration, it felt a bit chuggish (is that a word?) but nothing too bad. I pull into my driveway to find that my car now will not rev past 3000 RPM at a standstill.

Things to know:
-2004 330ci with 78,000 miles.
-None of my check lights are on.
-This is the only time I've ever had the fuel light come on in my 2 months of ownership.

I have a few theorys:

-I may have damaged my fuel pump. Keep in mind I only drove on the light for about 4 miles. Might that have just been enough?
-My idle control valve needs to be cleaned?
-My Mass Airflow Sensor is going bad?
-New fuel filter?
-It could have just been a complete coincidence and nothing is wrong with anything related to fuel.

What a bad day. :thumbdwn: I'm taking it to my Indy first thing tomorrow to get my OBD read. I'll post asap for those of you who care.

Thanks for reading! I needed to vent a bit.
 
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#2 ·
Until you get the codes scanned, all other thoughts are pure speculation....post results here, then we`ll have something to work with....
 
#3 · (Edited)
I realize that but I was hoping someone might have had similar experiences. I kinda wanted speculation to put my mind at ease. I will post the codes (or at least what the shop says) as soon as I get my car checked out tomorrow. Hopefully my Indy isn't booked for a week like they were last time something went wrong.
 
#4 · (Edited)
It never ceases to amaze me why the hell people drive around with their fuel tanks nearly on empty.

Fuel is used to keep the pump cool. It must be continually immersed to keep it that way.

When you drive around with a nearly empty tank, taking curves at speed with make your pump push air instead of fuel. Not only does this happen and cause it to overheat, but you'll mostly suck up sediment that resides at the bottom of the tank. The fuel filter will clog up faster than usual, which will cause the fuel pump to work harder.

All of this isn't very good for the livelihood of the fuel pump and WILL lead to its premature failure.

I never let my fuel gauge go below 1/4 due to these scenarios.
 
#5 ·
I learned the hard way. :dunno: I will never let it drop below 1/4 again.

Just wondering, when a fuel pump overheats, what goes wrong with it? I just find it hard to believe that it went bad after only 4 miles on the light. Perhaps the previous owner made the same mistake multiple times?
 
#6 ·
Formula 1, I vote for your fuel pump being bad. You have classic symptoms. But, it is a coincidence and has nothing to do with you low gas light. I have done it all the time in all my cars - driving till the low fuel light and then refilling. Never had a bad fuel pump. Most people do that with no ill effects. Cars are designed to do that. Low fuel is ok, no fuel is a different story - can cause some damage.

I'd change pump and filter. I changed my fuel pump as a preventative measure at 120K. I change fuel filter about every 60K

Good luck.
 
#7 ·
The OBC says I have about 50 estimated miles left on the tank. No problem.

...Somehow, now I only have 40 miles left on the computer.
The on-board computer is continually recalculating the range according to driving conditions and some measurement of instantaneous fuel consumption. A range of 50 miles can drop precipitously if, for example, you exit the highway onto a surface street where there's stop-and-go traffic.
 
#8 ·
I'd put a vote in for the fuel filter. It is possible that letting the fuel get that low caused an issue with your fuel pump as well. In general, it is a good idea to not let it bet below 1/4. That being said, I have run mine below "40 miles left" several times (have actually even gone past "0 miles left) and not had issues.

Possibly getting that low allowed some sediment to be sucked up and then caught in your fuel filter. Either way, changing the fuel filter is the easier/cheaper fix. If that doesn't fix it, then I would change the fuel pump. Good luck and keep us updated.
 
#9 ·
Running the fuel tank down to near empty does not hurt the fuel pump and will not cause it to pick up sediment. The fuel pump is already at the bottom of the tank so if there is any fuel it will be down in it and if there is any sediment its already there at the bottom too. In general its better not to let your fuel tank to run down near empty, but that's because you're likely to run out of gas and be stranded at some point.
You'll figure it out after its scanned.
 
#13 ·
+1 on bad gas, but the other thing that comes to my mind is the sparkplugs. 78k miles, 10-year old car, TWO MILE commute to work?! Maybe those are original plugs and they haven't had a good long run at full operating temperature in a long time. They could simply be fouled. One of the easiest DIYs is to pull a plug or two and take a look.
 
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