You keep going the route of a new pump. Granted, I understand what you are trying to get across, but from the beginning, you always said to test before throwing parts at the vehicle. That is what I am doing. You keep telling me to replace the pump, but so far the pump seems to be working ok according to the readings. Telling me I'm dicking around with it even though you were one of the first to say that diagnostics first, parts later is kinda rude (and I'm talking about the comments on youtube). Like I said, I did the pressure regulator test and that was the result. If the pump is pushing out 50psi and the fuel filter is pushing out 50psi, there must be more to it than just the fuel pump I would think. In the last video I posted I was getting a reading at the fuel filter. Even when we stepped hard on the gas and it felt like the vehicle was close to stalling, the pressure didn't drop at all, wouldn't that have been a red flag if the pump was not keeping up? Wouldn't it have dropped pressure?

I'm just trying to fix my car, simple as that. I tested the pump it seems to be running fine. If I buy a new pump and this doesn't fix the issue, what do I do then?

You already performed the test but don't want to admit it's a BAD fuel pump.

In one of your many videos, the pressure gauge showed ZERO pressure while you had someone crank the engine. Too me that mean a BAD fuel pump. What would that test suggest to you? A bad fuel regulator? A clogged fuel filter.

Don't know the sequence of videos you posted on youtube, but I assume the one with zero pressure was posted first and the one with normal pressure and the engine running was posted after you got the engine running.

It appears that you have a fuel pump that runs intermittently. Too me that means a BAD fuel pump.

c'mon guys, stop arguing...

Adrian, where are you standing at this point? Can you give us a quickie? i mean, a quick rundown of your issue in the next post, without me (i am too old to remember this!!) going back and rereading your threads... just a recap, like everything was fine, and one day something broke... it will help me, and probably many others, to regroup and offer more ideas... as i said a long time ago, i can deal with electronic crap in these cars, but i am too scared of juicy parts, and your ordeal is with the juicy things...

give us a quick rundown...

thanks...

Who's arguing????

Aww come on it's only 200+ post on this problems, not counting the 200 plus posts from the other thread.

Just trying to Help Adrian with his X.

my bad - silly me!!!:dunno:

all good... carry on...

:popcorn:

Quick rundown:

Vehicle was having issues taking off, i.e. acceleration problems. Receivd codes: P0171 and P0174. Replaced DISA valve, rubber boot, MAF sensor, still had issues. No vacuum leaks detected. Rented a fuel pressure tester, fuel pressure was zero. During the unscrewing of fuel pressure tester gauge, schrader valve broke. Decided to replace fuel rail once fixed. Replaced fuel pump with dismantler used pump, vehicle turned on great, no problems whatsoever. 2 weeks later, and about 2-300 miles, I replaced the fuel rail with a used one from ebay, as well as a MANN fuel filter. Vehicle ran great.

About 500 miles later, vehicle suddenly had issues with acceleration after coming to a stop at stop sign. Upallnight suggested that it probably wasn't a fuel related issue as the "cog" light lit up on dash, suggesting a tranny problem. Every time I turned the vehicle off and on again, the cog light would be off, wouldn't come back on unless I was having the acceleration issues which was every day. P0171 and P0174 came back. Replaced fuel pump with another used one, still had the issues. Was kept being told it is the fuel pump, even though I had replaced it yet again because pressure at schrader valve was sometimes 0 sometimes 20ish, 30ish at best. I purchased a cable and ran INPA and BMW Scanner 1.4 Nothing too bad, (except that fucking thermostat that I still haven't fixed because I'm waiting on fixing this fucking other dilema first), 31 errors from the LCM, possible issue, removed the glovebox and checked fuses, also under carpet where LCM was, no moisture or rust. Decided to replace the relays while I was at it.

Today I ran fuel pressure tests. First I connected the gauge to the fuel pump directly.
Pressure at fuel pump - YouTube

On this video the fuel pump is running fine, 50ish PSI, even when my brother steps on the gas and you can hear it struggling, the pressure doesn't fluctate.

On this video, the fuel gauge is on the fuel rail.
At fuel rail - YouTube

Fuel pressure is slowly going up, unfortunately the car then died (battery). But pressure never built up like at the fuel pump.

After the car charged for a bit, I pulled the bottom protective shield and connected the gauge to the fuel filter. Video 3:

Pressure at fuel filter - YouTube

Even with the car sputtering and not revving high, the pressure is maintained at +/- 50 psi. no fluctuation. Following bcredliner's advice, I tested to see the fuel pressure regulator function:
I wasn't going to jump the vehicle but I did have the vehicle running when I pinched the line. Pressure was still the same on the fuel filter, but the vehicle actually ran fine (redlined and everything) with the line pinched. Without it pinched, the vehicle sputtered and felt like it was going to die. I had already ordered a Beck/Arnley fuel filter from Amazon that came damaged, and am awaiting a replacement by Wednesday (1 day shipping, fml).

UpAllnight still says it is the fuel pump, as he has been adamant that a used fuel pump is shit, and maybe he is right, but 3 fuel pumps in a row is far fetched, but not impossible.

FUCK IT. I'm ordering the 100 dollar ebay pump once and for all to just see if it will fucking work. :( I'm sooooo agitated and tired of this issue, I just want my car fixed! FML. :banghead::banghead::banghead::banghead::banghead: :banghead::banghead::banghead::banghead::banghead: :banghead:

If you read your post I did not tell you to replace the fuel pump. I said you had another issue when the COG light came on. You replace the fuel pump on your own with another used fuel pump.

When the key is turned on you should have immediate pressure in the rail, which you don't have , but was slowly rising which would point to a BAD fuel pump.

Labor day, think I'm going to the lake and enjoy the last days of summer and forget about Xoutpost for a while.

See Ya and GL.

Thanks for the recap...very helpful in catching up what has transpired.

It sounds as if you've used three different fuel pumps. Is that correct? And now you're ordering a fourth (because the previous ones were used)? I'd be very surprised if the new fuel pump ends up resolving the issue. Three bad fuel pumps in a row? Seems very unlikely.

What is the sequence of fuel flow? I assume it's fuel pump -> fuel filter -> fuel rail? What concerns me is pressure is fine (I assume 50 PSI is within spec) at the fuel pump and filter but not at the fuel rail. Did I interpret this correctly from the videos? The concern would be the no / slowly rising pressure at the fuel rail. Common sense tells me it should prime to 50 PSI when the key is turn on (perhaps it was low due to a discharged battery as you said the battery soon expired during that particular test?) Is there anything between the fuel filter and fuel rail which may be restricting flow? Perhaps debris of some sort?

You also mentioned a stumbling when attempting to rev the engine (Is this is the problem you're trying to resolve?) and the P0171 and P0174 codes were codes I experienced with a bad MAF. I know you replaced the MAF but the symptoms you're describing sound a lot like the issues I had when I had a bad MAF. May I suggest you disconnect it as a quick and dirty way to rule it out as the problem (or an air leak post MAF)? I'd hate for this to be the cause of your problem and never considered as you have already replaced it. Though to me everything looks like a nail (MAF) because that's what I experienced first hand. But it couldn't hurt...takes only a few seconds and it's free. It wouldn't explain the lack of pressure at the fuel rail though.

I understand that the battery died during the fuel pump test, this can be the reason why you got a low psi reading during the test. P0171 and P0174 normally are MAF related. Why you dont test the wires or signals at the MAF and Computer ends?

We are only testing what the fuel pump and filter do when the return is pinched. The engine should not be running.

If the fuel pressure rises quickly when you pinch the return line it indicates the regulator is likely at fault.

If the fuel pressure stays the same it indicates the fuel pump is likely at fault.

In the test you did with the engine running the gauge moved very little and slowly. assuming a test without the engine running the results would indicate the cause of your problem is likely the fuel pump.

Run the test with the engine not running.

The battery should be at full charge.