[MooreBoost]

For the past two weeks my '10 335i has idled terribly first thing in the morning when it's cold. It sounds like it's missing and shakes rather badly. As soon as I give it any amount of gas, it runs perfectly.

It idles perfectly when it's hot.

Thoughts?

Update in post 6. Resolved in post 12.

[Jeff@TopGearSolutions]

Does it smell like fuel at start up?

First thing I'd do is pull the plugs and see if they are fouled with fuel or oil.

Fuel would be an indication of bad injectors, oil would likely be valve cover gasket.

If they are fine and the plugs are in good shape at the correct gap then I'd start to look elsewhere.

[335e92tx]

I had two probs that had almost the same EXACT symptoms. At 100K, began to get rough cold starts with raw fuel smell. Would clear up after 30secs. Replaced injectors and solved prob.

Within 2 months prob somewhat returned but slightly 'better'... not as consistent. Ended up being FP number 4. But it did throw high pressure fault codes I think..

[Jeff@TopGearSolutions]

Originally Posted by 335e92tx

I had two probs that had almost the same EXACT symptoms. At 100K, began to get rough cold starts with raw fuel smell. Would clear up after 30secs. Replaced injectors and solved prob.

Within 2 months prob somewhat returned but slightly 'better'... not as consistent. Ended up being FP number 4. But it did throw high pressure fault codes I think..

Funny you say that, I was going to remark on the HPFP being a possible culprit too but it's hard to diagnose without a code or datalogging capability.

[MooreBoost]

I don't think I've ever smelled fuel, but will pay more attention.

I had the VCG done very recently.

90k on the clock.

[MooreBoost]

Pulled the following codes-

Active Codes

29F2 - Fuel high-pressure system, fuel pressure
2B2C - Fuel high-pressure, plausibility, cold start
(Plus misfires)

Shadow Codes

2FCA
2FDA
2FDB

Is this further evidence of HPFP failure? Thanks.

[335e92tx]

Originally Posted by MooreBoost

Pulled the following codes-

Active Codes

29F2 - Fuel high-pressure system, fuel pressure
2B2C - Fuel high-pressure, plausibility, cold start
(Plus misfires)

Shadow Codes

2FCA
2FDA
2FDB

Is this further evidence of HPFP failure? Thanks.

I think your there bud

http://www.bimmerfest.com/forums/sho...92&postcount=3
2FCA and 2FDA are also shadow codes that show up after any software code update and have to do with hpfp not priming correctly, but most people get those codes even on brand new pumps and they rarely cause any issues.

[MooreBoost]

Taking the car to do the dealer on Thursday in hopes that it's the HPFP and that they cover it under the extended warranty.

Should I load my stock tune or keep the MHD on there?

Specifically, I don't want MHD on there for obvious reasons, but I also don't want to clear the codes so that the dealer is able to see them.

[335e92tx]

Originally Posted by MooreBoost

Taking the car to do the dealer on Thursday in hopes that it's the HPFP and that they cover it under the extended warranty.

Should I load my stock tune or keep the *** on there?

codes still should be present - ugh, but come to think of it, theres like a un-coded fault that will still be present too and that indicates and aftermarket tune. You might need to clear codes now and then pull MHD and then drive it for a couple of days.

g/l

[MooreBoost]

Well, will the codes didn't come back before my appointment today, after reloading the stock tune.

The service rep mentioned the HPFP after I described the symptoms, and said they would warranty it if the codes came back. So that's good news.

Just have to wait now.

[335e92tx]

good deal -

[MooreBoost]

The car finally threw another fuel pressure code. I took it back in and they warrantied the HPFP. That seems to have resolved the issue.

[HB E90]

I know this is a very old thread but Its exactly what I had going on on my 2010 E90 335. I suspected the HPFP but after reading this I was convinced that was it. I scored a NIB OEM HPFP from another member here for $400 and did it myself. All good now. THANK YOU

[Saif2018]

Originally Posted by HB E90

I know this is a very old thread but Its exactly what I had going on on my 2010 E90 335. I suspected the HPFP but after reading this I was convinced that was it. I scored a NIB OEM HPFP from another member here for $400 and did it myself. All good now. THANK YOU

[Maxmil982]

Stealer actually for the win

[Maxmil982]

Leaking injectors maybe