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Discussion Starter · #1 ·
This one got me stumped for now. Help/Experiances appreciated. My check engine light came on about 3 weeks ago. Code 174 evap. I reset and it came back in 2 days. So I reset every other day till I can get to it.
So yesterday I drove my 03 - 325xi to my brothers for a mothersday cookout. Seemed to run just fine. Light was on. Previously in the week I did notice some slight misfire though. Slight at takeoff. Anyway, I get up this morning and go to leave for work and the car just turns over with a sound like no spark or fuel? It would not start. So I took my truck to work. I come home and check the codes. PO301, PO303,PO305 along with the 174. I cleared them and tried to start. She fired right up. Smooth no miss at all. S I decided to get new plugs and change. I did that and fired her up. Nice smooth sound, Job well done. Hopefully this would cure the slight misfire. I let it run for 10 minutes or so while I cleaned up tools and myself. Everything seemed good. So I decided to shut off and restart before a test drive. She would not start and still won't start. No codes at all eaither. It still has that engine cutoff sound.
I am wondering if somthing is telling it to not run. With no new codes It is hard to determine.
Any thoughts?

thanks
Joe:banghead:
 

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Spark plugs do not fix issues. Our modern spark plugs either work or they dont , new ones arent any better then old ones , if the old worked.

You problem wost likely lies somewhere else. Please spend a few dollars and get your car properly diagnosed with proper software , the generic stuff that you use isnt ever gonna help you and will only confuse you

Do you hear the fuel pump price when key in 2nd position? If not, check the voltage at the fuel pump plug.

Its very difficult to say what your problem is, it could be so many things from as simple as battery to coil packs, to O2 sensors to maf, to fuel pump to crank sensor etc etc
 

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$3 can of starting fluid and a 2 second shot inside the air filter box, if the car starts and dies, you have a fuel problem.

Fuel pumps in these car are on borrowed time after about 7-8 years.

Also check the first link below in my signature for more info on misfires.

Also replace the fuel filter and check the fuel pressure regulator vacuum hoses as well.
 

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Discussion Starter · #4 ·
Sorry for the delay I finally got to look at the car.



Nice Call jfoj

$3 can of starting fluid and a 2 second shot inside the air filter box, if the car starts and dies, you have a fuel problem.
Right on the spot.
I shot it with fluid and she kicked over and fired up. Of course very sloppily.... lol is that even a word.

Since I have been very fortunate to drive this car with no motor problems for 177,000 miles - I need pointed to locations of these parts if you will. Meanwhile I'll try and find them.
I've worked on every car I had my whole life. Pretty good at it.

Anyway - I am sure there is a fuel pump relay... Guessing under hood drivers fire wall. Is that close? It might not be working or the computer could be cutting it off.... What would tell the computer to do that?

fuel pressure regulator vacuum hoses - Those I don't know about.... Hunting now....

Fuel filter - searching for that too..... I probably should have changed that about 100,000 miles ago.

Thanks again
joe
 

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Discussion Starter · #6 ·
Took off the fuel filter today and hardly any gas coming out. Time to change anyway.
I believe the fuel pump died. Will check voltage at the pump tomorrow and replace if needed.
 

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Do not bother checking the Voltage to the pump, if your car has the original fuel pump, you need to replace it.

Fuel pump relay is behind the glove box, the entire glove box needs to be removed to access it. Not hard, about 6 screws. Relays do not bad, but fuel pumps rarely last more than 7-8 years, some get lucky and they last longer.

Pull the bottom rear seat, the fuel pump is on the passenger side.

3 Phillips screws to remove the access plate after you cut the tabs on the sound proofing.
 

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Discussion Starter · #8 · (Edited)
Since was so easy to check voltage at the fuel pump I did. I called the dealer first to see what there price was and he said which one.
There are 2 fuel pumps Primary and secondary. 1 on each side. Nobody else has this? Both only have 4.9 volts going to them and neither seem to run. So I am leaning toward a voltage issue?
They both could not have died at the same time unless there was a power surge. And I didn't notice anything.
What do you think? These should have 12 volts correct. I will try the small battery charger on them to see if they work.
I really don't want to replace parts if not needed.
 

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Dude, put on the brakes!!!

Do not hook up a battery charger to test anything!!

Here is the deal, you are a BMW noob, not a problem, just listen.

1. Cannot measure battery Voltage easily for the fuel pump with the key on. The reason is the fuel pump relay is only on for 2-3 seconds to prime the fuel line until the engine actually starts. So you will not see 12 Volts at the pump input but for a few seconds with the key in the on position.

2. What you are probably measuring is the Voltage for the fuel gauge from the dash. Just so you know your car has 2 fuel level senders.

3. Your car does have 2 fuel pumps, most BMW's do. The drivers side pump is a passive, non electric, siphon pump that uses return fuel to siphon fuel from the drivers side to the passenger side, this pump (also known as jet pump) rarely fails. The passenger side pump is probably considered the "primary" pump, it is electric, they fail usually after 7-8 years. This is the one that needs to be replaced.

4. Even if you replace your fuel pump and you still have issues, your fuel pump needs to be replaced anyway, unless you know for a fact is has been replaced before. If you had to cut the sound proofing tabs to access the pump, it is original.

Suggest you get a replacement pump from my favorite BMW supplier listed in my signature below, they are in NE, so you may be able to place the order today and ask for overnight shipping and have it tomorrow cheaper than you could get it from you local dealer. My favorite source would is VERY fair on shipping prices and standard shipping is free this month, so I doubt they would charge more than $10 for overnight?
 

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Discussion Starter · #10 ·
I tested the relay and it is good. I even swaped it with another with same numbers.
My first thoughts was the fuel pump but I don't waste money anymore changing out things without testing them.
It is official. The fuel pump is dead. Had to test it. I used a 12 volt battery to test not the charger.
Thanks for the info jfoj..... New pump will be here at 8am... I'll post the results.
 

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Discussion Starter · #11 ·
New pump was the issue. The filter was pretty much clogged, That's probably why the pump burned up...
Pluggs were needed pretty bad too, the old ones were original bmw pluggs. 179,000 miles and runs really strong, I would say that is not to bad for those parts to last.
My testing methods are old fashoned but they do work. I have been working on cars for 35 years and built wiring harnesses for them for 15. This is the first BMW that I have had problems with and worked on, so it was a little new to me but not much different. Better engineered for sure.
159 pump, 69 filter and 30 for pluggs.... What would it cost to buy all the new diagnostic equipment or take it to a dealer to fix it. Probably 500 plus.

Anyway were back in buisness, thanks for the advise jfoj and BlockedOut
 
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