[loweredram]

I did some searching but wanted to ask the more experienced guys a question on the 335i LPFP. I was getting some mixture control codes 2e90 and 2e91 and occasional P2aaf with SES light when running cobb E30 or 3 gal of E85 to 13 of 91 ACN on cobb stage 2+fmic aggressive . Long story short I changed the pre cat o2 sensors and my LPFP sensor and codes are gone. My question is while doing logs running 3 of E85 with 13 of 91 my LPFP is getting as low 50psi. Ive heard 50 is the magic number that can cause problems. I don't know the range the pump should operate in new. should it ever drop below 72psi? should I just get a new one is this one on the way out? My car is FBO with 60k on it.

thanks guys

[Bimmer305]

Originally Posted by loweredram

I did some searching but wanted to ask the more experienced guys a question on the 335i LPFP. I was getting some mixture control codes 2e90 and 2e91 and occasional P2aaf with SES light when running cobb E30 or 3 gal of E85 to 13 of 91 ACN on cobb stage 2+fmic aggressive . Long story short I changed the pre cat o2 sensors and my LPFP sensor and codes are gone. My question is while doing logs running 3 of E85 with 13 of 91 my LPFP is getting as low 50psi. Ive heard 50 is the magic number that can cause problems. I don't know the range the pump should operate in new. should it ever drop below 72psi? should I just get a new one is this one on the way out? My car is FBO with 60k on it.

thanks guys

Search for: Fuel Scalar

[135Pats]

Stock pump is likely getting tired at that mileage as well. I just replaced the entire bucket when I added the FFTEC pump.

Generally speaking you don't want to see pressure fall below 50PSI or it drags the high pressure side down with it.

[Bme30]

My original pump at 50k miles would drop to 42psi on 93 oct.
Replaced with a new lpfp and rocking 78psi all day. Time for the replacement. I had all the exact codes and issues you are experiencing. All problems fixed!!!

And I'm Fbo also. So literally we have had the same issues. Hope this helps.

[loweredram]

Originally Posted by Bme30

My original pump at 50k miles would drop to 42psi on 93 oct.
Replaced with a new lpfp and rocking 78psi all day. Time for the replacement. I had all the exact codes and issues you are experiencing. All problems fixed!!!

And I'm Fbo also. So literally we have had the same issues. Hope this helps.

Thanks man! That's exactly the info I was hoping to get. I just ordered the pump after reading your post. I was outside logging the lpfp at idle and I could get it to spike down to 66 psi just from revving the engine.

I luckily found a place selling the OEM pump (VDO) complete on sale for the next 3 days for $211.00.

I've read a few diy on removing and replacing the pump doesn't look to complicated.

Thanks again!!

Share the link!! I've never seen the OEM lpfp go for that cheap.

[loweredram]

[QUOTE=FCobra94;15435845]Share the link!! I've never seen the OEM lpfp go for that cheap.[/

http://www.ebay.com/itm/300671313277

I called them directly they are based out of San Diego. AJ was the person I talked to stated its 100% OEM VDO manufactured BMW lpfp as advertised with fuel level sending unit as pictured .

[Mit_Boost]

Originally Posted by loweredram

My question is while doing logs running 3 of E85 with 13 of 91 my LPFP is getting as low 50psi. Ive heard 50 is the magic number that can cause problems. I don't know the range the pump should operate in new. should it ever drop below 72psi? should I just get a new one is this one on the way out? My car is FBO with 60k on it.

thanks guys

3 Gal of True E85 mixed with 13 Gal of 91 should be 24% Ethanol and be spot on with the COBB E30 OTS Maps (specifically, the Fuel Scalar). What you need to do is take a data log that captures fueling specific data, here's the list I would use:

1. STFT (Bank 1)
2. STFT (Bank 2)
3. LTFT (Bank 1)
4. LTFT (Bank 2)
5. Fuel HPFP Requested
6. Fuel HPFP Actual
7. Fuel LPFP Requested
8. Fuel LPFP Actual
9. Lambda (Bank 1)
10. Lambda (Bank 2)
11. Lambda Requested (Bank 1)
12. Lambda Requested (Bank 2)
13. RPM
14. TPS Actual
15. Load Requested
16. Load Actual
17. Timing Correction Cylinders 2-5 (Pick 1, I don't like to Log off the "ends")
18. Timing Cylinders 2-5 (Pick a different one that you used for Timing Corrections)
19. WGDC
20. Boost

What this list should show us is if your Target Values are correct, and if your Actual Values are achieving or under performing. When everything is running right, during WOT your Low Pressure should hold 72 psi and the High Pressure should be consistently above 2,000 psi. Your STFTs should be sub-25%, and the LTFT should be sub-20%.


Depending on what's off, we should be able to diagnose what's wrong (Ethanol Content is too High, LPFP has started to die, etc) and hopefully diagnose.

[Bme30]

Originally Posted by loweredram

Thanks man! That's exactly the info I was hoping to get. I just ordered the pump after reading your post. I was outside logging the lpfp at idle and I could get it to spike down to 66 psi just from revving the engine.

I luckily found a place selling the OEM pump (VDO) complete on sale for the next 3 days for $211.00.

I've read a few diy on removing and replacing the pump doesn't look to complicated.

Thanks again!!

You will be happy with the new pump. If pretty straight forward for the replacement. A little bit of a pain in the ass, but can easily be done. Just take your time. Also make sure you are low on fuel. I waited till my light came on and made the job easy.
After you replace the pump run some logs and reset adaptations.
When logging for me the initial surge of going wot I notice my fuel pressure drop to 66psi, but instantly recover to 78psi ( completely normal ).
May car finally runs great again!!!

[loweredram]

Originally Posted by Mit_Boost

3 Gal of True E85 mixed with 13 Gal of 91 should be 24% Ethanol and be spot on with the COBB E30 OTS Maps (specifically, the Fuel Scalar). What you need to do is take a data log that captures fueling specific data, here's the list I would use:

1. STFT (Bank 1)
2. STFT (Bank 2)
3. LTFT (Bank 1)
4. LTFT (Bank 2)
5. Fuel HPFP Requested
6. Fuel HPFP Actual
7. Fuel LPFP Requested
8. Fuel LPFP Actual
9. Lambda (Bank 1)
10. Lambda (Bank 2)
11. Lambda Requested (Bank 1)
12. Lambda Requested (Bank 2)
13. RPM
14. TPS Actual
15. Load Requested
16. Load Actual
17. Timing Correction Cylinders 2-5 (Pick 1, I don't like to Log off the "ends")
18. Timing Cylinders 2-5 (Pick a different one that you used for Timing Corrections)
19. WGDC
20. Boost

What this list should show us is if your Target Values are correct, and if your Actual Values are achieving or under performing. When everything is running right, during WOT your Low Pressure should hold 72 psi and the High Pressure should be consistently above 2,000 psi. Your STFTs should be sub-25%, and the LTFT should be sub-20%.


Depending on what's off, we should be able to diagnose what's wrong (Ethanol Content is too High, LPFP has started to die, etc) and hopefully diagnose.

Thanks for the info . I will set these in cobb and do some runs tomorrow. I forgot the format I was supposed to use to post cobb data log files . I thought the cobb E30 map required at least 30% E85 to run properly?

[loweredram]

Originally Posted by Bme30

You will be happy with the new pump. If pretty straight forward for the replacement. A little bit of a pain in the ass, but can easily be done. Just take your time. Also make sure you are low on fuel. I waited till my light came on and made the job easy.
After you replace the pump run some logs and reset adaptations.
When logging for me the initial surge of going wot I notice my fuel pressure drop to 66psi, but instantly recover to 78psi ( completely normal ).
May car finally runs great again!!!

How does your new LPFP do running E85 ?

[boostaholic786]

I was having very similar issues AFTER I installed my walbro 465lph E85 rated pump....But we switched out the pump with another walbro out of my buddies car, did the same thing... Put the stock LPFP back in, the car did the same thing...So I think im having a lot BIGGER issues than just my fueling and is at the dealership as we speak....I have a feeling its the rod bearings or something to do with the crankshaft. The last time I took my car in it they replaced the crankshaft sensor and I thought I would be good to go but the next day I took it back up to the dealership and has been there for the past month................IM BECOMING VERY IMPATIENT, ESPECIALLY AFTER I DEMODDED THE CAR, REMOVED BACKEND FLASH, REMOVED TUNE, and I have cam codes, vanos codes inlet and outlet, crankshaft codes, low boost mode engaged, and I think there is a couple more.. So I have no idea why its taking so long but im getting very angry since this is a SB and 99% of the techs/friends I have talked to, said its probably either the vanos or the rod bearings/journal bearings...im just waiting till I get that phone call and them saying everything is fixed, please come pick your car up because IM going thru "going fast" withdrawls haha

[Mit_Boost]

Originally Posted by loweredram

Thanks for the info . I will set these in cobb and do some runs tomorrow. I forgot the format I was supposed to use to post cobb data log files . I thought the cobb E30 map required at least 30% E85 to run properly?

The E30 Maps are designed for up to 30% Ethanol, so if you were running a 24% blend then your trims should've been EASILY in check if everything was running correctly.

You would probably start having issues if you tried running the E30 Map with a 35% or greater concentration. You could run the E30 Fuel Scalar on a Pump Gas Map, it just wouldn't be wise since you'd constantly have negative fuel trims (think of it like a sign of "over" fueling, so the DME is cutting back how much fuel it needs).

Originally Posted by loweredram;15436188[url

http://www.ebay.com/itm/300671313277[/url]

I called them directly they are based out of San Diego. AJ was the person I talked to stated its 100% OEM VDO manufactured BMW lpfp as advertised with fuel level sending unit as pictured .

Thanks yo! Will be picking one up shortly!

Originally Posted by boostaholic786

I was having very similar issues AFTER I installed my walbro 465lph E85 rated pump....But we switched out the pump with another walbro out of my buddies car, did the same thing... Put the stock LPFP back in, the car did the same thing...So I think im having a lot BIGGER issues than just my fueling and is at the dealership as we speak....I have a feeling its the rod bearings or something to do with the crankshaft. The last time I took my car in it they replaced the crankshaft sensor and I thought I would be good to go but the next day I took it back up to the dealership and has been there for the past month................IM BECOMING VERY IMPATIENT, ESPECIALLY AFTER I DEMODDED THE CAR, REMOVED BACKEND FLASH, REMOVED TUNE, and I have cam codes, vanos codes inlet and outlet, crankshaft codes, low boost mode engaged, and I think there is a couple more.. So I have no idea why its taking so long but im getting very angry since this is a SB and 99% of the techs/friends I have talked to, said its probably either the vanos or the rod bearings/journal bearings...im just waiting till I get that phone call and them saying everything is fixed, please come pick your car up because IM going thru "going fast" withdrawls haha

Damn Best of luck to you...let us know how it goes!

[loweredram]

Originally Posted by Mit_Boost

The E30 Maps are designed for up to 30% Ethanol, so if you were running a 24% blend then your trims should've been EASILY in check if everything was running correctly.

You would probably start having issues if you tried running the E30 Map with a 35% or greater concentration. You could run the E30 Fuel Scalar on a Pump Gas Map, it just wouldn't be wise since you'd constantly have negative fuel trims (think of it like a sign of "over" fueling, so the DME is cutting back how much fuel it needs).

Got it. And thanks for the info.

[Bme30]

Originally Posted by loweredram

How does your new LPFP do running E85 ?

GREAT!

I have recently added the walbro 255 so i can backend flash and run higher concentrations of e85.

running E30 my lpfp by it self ran great.

[BMWM.D.]

Originally Posted by Mit_Boost

The E30 Maps are designed for up to 30% Ethanol, so if you were running a 24% blend then your trims should've been EASILY in check if everything was running correctly.

Not to be argumentative, but Cobb recommends 30% ethanol (mixed with a minimum of 91 octane) to support the boost and timing the E30 Race Map commands. The fuel trims should be just fine with ~E25 in the tank, but I wouldn't be so sure about timing correction issues. Keep in mind we're in CA and have crappy ACN 91 octane we have to mix our E85 with.

[Mit_Boost]

Originally Posted by BMWM.D.

Not to be argumentative, but Cobb recommends 30% ethanol (mixed with a minimum of 91 octane) to support the boost and timing the E30 Race Map commands. The fuel trims should be just fine with ~E25 in the tank, but I wouldn't be so sure about timing correction issues. Keep in mind we're in CA and have crappy ACN 91 octane we have to mix our E85 with.

I understand that, but the OP is having trouble with Fuel Pressure (specifically LPFP), which is why I mentioned Fueling Specific Parameters (Target vs. Actual Pressure, STFT/LTFT Trims, etc)

[BMWM.D.]

Originally Posted by Mit_Boost

I understand that, but the OP is having trouble with Fuel Pressure (specifically LPFP), which is why I mentioned Fueling Specific Parameters (Target vs. Actual Pressure, STFT/LTFT Trims, etc)

What you mentioned is very good advice for tracking down mixture code issues, fuel pressure fault codes, etc. If your fuel pressure drops below a certain level, your fueling isn't going to be correct. One of the great things about the N54 is that all these PIDs can be easily logged.

Dropping fuel pressure doesn't have too much to do with the fuel scaler tables, though. Just wanted to make it clear that guys shouldn't be putting much less than 30% ethanol in with that race map from an octane/knock resistance standpoint.

[loweredram]

[QUOTE=FCobra94;15438681]Thanks yo! Will be picking one up shortly!




mine will be here today. I will do a side by side comparison and let you know.

[QUOTE=loweredram;15443839]

Originally Posted by FCobra94

Thanks yo! Will be picking one up shortly!




mine will be here today. I will do a side by side comparison and let you know.

Yeah, ordered one last night before the sale was over. A comparo would be much appreciated though...not going to be installing mine until spring time anyway.

[46m3csl]

How do you test the pumps for psi?