[dx1541]

Thought I'd share my second experience with a new hpfp change done yesterday after experiencing p29dc code being thrown again.

Only about 7 months ago I replaced my hpfp with the newest revision after experiencing half engine light being thrown immediately after WOT. Modifications are full FBO running JB4 G5 with a customized Cobb back end flash on E70 running map 7 all the time.

As mentioned then, I was experienced hpfp crashing on the logs taken despite having a 450 l/hr in tank E85 pump installed and running at over 75psi. No long cranks whatsoever in the morning but only hpfp diving ( and it was doing so even with reduced percentage of e85 and eventually 93 pump alone )

29DC is being caught on the COBB error code history and eventually a new hpfp fixed it , till came Friday night before. Car is only driven on the weekends and runs pure E70 all the time. As much as I can remember I had no more codes thrown after the hpfp replacement months ago.

Back to Friday night where I suddenly experienced half engine light being thrown on wot and was startled to see P29DC being recorded on the Cobb unit, again? Wtf!

I am lucky a friend of mine runs a parts distributor ship for mercedes, bmw and audi and immediately had him sent me another new hpfp unit. ( costs usd 350 here by the way ) and I had the car sent to my mechanic who did the last changeover. He said , what? Another one? , yeah, let's see I told him.

1 hour was how long it took for the changeover ( he does it with only the TB removed ) and that night itself, did a run and log again, and yup! Problem fixed again and here I would like to advise those who have had this issue to be wary on the extended use of E85 on our cars.

Not sure if there are different grades of ethanol between what is in the US and over here, ( ours is cane based ) but then again my source is blended in small quantities by a fellow friend at anytime I require so.

Having insufficient flow on high power levels with E85 on our hpfp is already somewhat of a problem but I truly believe and have proven so here that the content of ethanol does wreck the internals of our fragile hpfp and BMW have not addressed a solution for use with Ethanol content.

Thank goodness the price of a replacement hpfp unit is still cheap in comparison to other parts but I intend to expedite by ST build to run on pump or race gas exclusively. Who knows what the E85 could ruin next in our motors.

Oh just when I thought I fixed a major issue, I got 4 error messages when reversing the car out of the garage yesterday, DBC, FTM, ABS and start assistance inactive ! It's on permanently and further probing is pointing towards a DBC ABS hydro unit failure! Gosh! What's next!

[Indo Rider]

If running e70 consistantly made a hpfp fail after 7 months (or less since you don't even drive it daily) a lot more people would be reporting failures these days. I have about 3 years on my hpfp running e40+ and ~e70 for nearly the last year. And its my daily. No signs of issues for me...

[Julian2485]

Originally Posted by dx1541

Thought I'd share my second experience with a new hpfp change done yesterday after experiencing p29dc code being thrown again.

Only about 7 months ago I replaced my hpfp with the newest revision after experiencing half engine light being thrown immediately after WOT. Modifications are full FBO running JB4 G5 with a customized Cobb back end flash on E70 running map 7 all the time.

As mentioned then, I was experienced hpfp crashing on the logs taken despite having a 450 l/hr in tank E85 pump installed and running at over 75psi. No long cranks whatsoever in the morning but only hpfp diving ( and it was doing so even with reduced percentage of e85 and eventually 93 pump alone )

29DC is being caught on the COBB error code history and eventually a new hpfp fixed it , till came Friday night before. Car is only driven on the weekends and runs pure E70 all the time. As much as I can remember I had no more codes thrown after the hpfp replacement months ago.

Back to Friday night where I suddenly experienced half engine light being thrown on wot and was startled to see P29DC being recorded on the Cobb unit, again? Wtf!

I am lucky a friend of mine runs a parts distributor ship for mercedes, bmw and audi and immediately had him sent me another new hpfp unit. ( costs usd 350 here by the way ) and I had the car sent to my mechanic who did the last changeover. He said , what? Another one? , yeah, let's see I told him.

1 hour was how long it took for the changeover ( he does it with only the TB removed ) and that night itself, did a run and log again, and yup! Problem fixed again and here I would like to advise those who have had this issue to be wary on the extended use of E85 on our cars.

Not sure if there are different grades of ethanol between what is in the US and over here, ( ours is cane based ) but then again my source is blended in small quantities by a fellow friend at anytime I require so.

Having insufficient flow on high power levels with E85 on our hpfp is already somewhat of a problem but I truly believe and have proven so here that the content of ethanol does wreck the internals of our fragile hpfp and BMW have not addressed a solution for use with Ethanol content.

Thank goodness the price of a replacement hpfp unit is still cheap in comparison to other parts but I intend to expedite by ST build to run on pump or race gas exclusively. Who knows what the E85 could ruin next in our motors.

Oh just when I thought I fixed a major issue, I got 4 error messages when reversing the car out of the garage yesterday, DBC, FTM, ABS and start assistance inactive ! It's on permanently and further probing is pointing towards a DBC ABS hydro unit failure! Gosh! What's next!

I had those same 4 error codes

[dx1541]

Originally Posted by Julian2485

I had those same 4 error codes

what was the problem at the end?

[dx1541]

Originally Posted by Indo Rider

If running e70 consistantly made a hpfp fail after 7 months (or less since you don't even drive it daily) a lot more people would be reporting failures these days. I have about 3 years on my hpfp running e40+ and ~e70 for nearly the last year. And its my daily. No signs of issues for me...

I think the problem is 2 things for mine, I don't drive mine daily, maybe once or twice a week thus one tank of E85 sits in my tank for a month or maybe more plus we have extremely high humidity over here thus the ethanol may absorb lots of moisture while just sitting there.

But reason why I posted this was to let people know what P29DC fault really points to, the hpfp itself.

[pwr hungry]

I think your big issue is that it sits in the tank and lines for so long. The ethanol gumming is my main concern for running it in my car as I don't drive it but a couple times a week at best myself. Best of luck getting it all sorted out. Did you pull the last pump apart and see if there was any debris or damage?

[DR-JEKL]

Why not run lower amounts of ethanol the, E40 for instance?

[Julian2485]

Originally Posted by dx1541

what was the problem at the end?

Honestly the problem was every time I disconnected the battery I would get those faults a BMW mechanic told me turn the steering wheel all the way left then all the way right and codes came off lol

[C.Pop]

No offense but correlation does not imply causation. The HPFP is a hit & miss sort of thing and while I acknowledge that the use of ethanol does increase flow demand from the pump, lots of HPFP's have failed with very low mileage on them even strictly on pump gas.

I've been running e50 for a couple of years and recently stepped up to e60. The car has 97k on it. HPFP is starting to get tired but still okay.

You got a bum hpfp, your fuel is extremely poor quality, or there is another reason you're burning through them, line obstructions or similar thing (which wouldn't show up in lpfp logs).

[dx1541]

Originally Posted by C.Pop

No offense but correlation does not imply causation. The HPFP is a hit & miss sort of thing and while I acknowledge that the use of ethanol does increase flow demand from the pump, lots of HPFP's have failed with very low mileage on them even strictly on pump gas.

I've been running e50 for a couple of years and recently stepped up to e60. The car has 97k on it. HPFP is starting to get tired but still okay.

You got a bum hpfp, your fuel is extremely poor quality, or there is another reason you're burning through them, line obstructions or similar thing (which wouldn't show up in lpfp logs).

I don't but then again I do admit i do doubt the quality of my ethanol for I don't think the pump 93 that I use is bad at all ( shell v power ) , bum hpfp? Nah, not on the latest variation bmw sells, more like I have ethanol sitting in my tank too long rather than being a daily driver.

We'll see how it goes with the second unit ( or was it third? ) now.

[CHECKERED]

Originally Posted by pwr hungry

I think your big issue is that it sits in the tank and lines for so long. The ethanol gumming is my main concern for running it in my car as I don't drive it but a couple times a week at best myself. Best of luck getting it all sorted out. Did you pull the last pump apart and see if there was any debris or damage?

X2

are there any hints of rust or garnish on the inside of the pump?

[Bme30]

I have been running 40-60% e85 for almost 2 years and my hpfp is running great still.