[Slavsky]

Hi all
I just replaced my high pressure fuel pump in my 2011 e90 n55 335i x drive, it recently went and stopped giving fuel injection and threw all sorts of codes. Got it all back together and took it out for a drive and after warmed up and all I did a couple pulls and it simply didn't feel as hard as it did before (stage 2+ fbo, and xhp stage 3). Went back home and noticed I had a rattle coming from the turbo side of the engine, now before on start up, in particular cold starts I had a rattle but it ran fine and pulled great, rattle would go away once it warmed up, now it seems to be there even at temp. I also replaced coil packs and spark plugs (ngk 2 step colder). And through the process I have ZERO codes thrown right now.

Any insight on what's going on??
Could this be the infamous wastegate rattle and it's all going bad at the perfect time I replaced my hpfp, and THATS why my pulls aren't as hard? I'm really not sure.

Thanks guys.

[DiFFv1]

Originally Posted by Slavsky

Hi all
I just replaced my high pressure fuel pump in my 2011 e90 n55 335i x drive, it recently went and stopped giving fuel injection and threw all sorts of codes. Got it all back together and took it out for a drive and after warmed up and all I did a couple pulls and it simply didn't feel as hard as it did before (stage 2+ fbo, and xhp stage 3). Went back home and noticed I had a rattle coming from the turbo side of the engine, now before on start up, in particular cold starts I had a rattle but it ran fine and pulled great, rattle would go away once it warmed up, now it seems to be there even at temp. I also replaced coil packs and spark plugs (ngk 2 step colder). And through the process I have ZERO codes thrown right now.

Any insight on what's going on??
Could this be the infamous wastegate rattle and it's all going bad at the perfect time I replaced my hpfp, and THATS why my pulls aren't as hard? I'm really not sure.

Thanks guys.

Tighten the westgate 7-10mm Midget wrench from sears. If rattle persists, Time for a new westgate/Bung

[JJaber]

Originally Posted by DiFFv1

Tighten the westgate 7-10mm Midget wrench from sears. If rattle persists, Time for a new westgate/Bung

Can you replace the waste gate on the N55? I noticed the same issue with mine...waste-gate rattle is louder/more audible on acceleration AND deceleration and the car doesn't pull like it used to.

[xxMike61]

I've had a rattle for a while now and boost was always a 2-3 psi from target all throughout the pull. Installed GFB DV to see if anything helped but I dont see any difference in the logs. I do have stock FMIC connections so that might be it? But the rattle is driving me crazy, I can't drive with my windows down because its so noticeable.

[JJaber]

Originally Posted by xxMike61

I've had a rattle for a while now and boost was always a 2-3 psi from target all throughout the pull. Installed GFB DV to see if anything helped but I dont see any difference in the logs. I do have stock FMIC connections so that might be it? But the rattle is driving me crazy, I can't drive with my windows down because its so noticeable.

Do you notice your BOV sounding more noticeable from inside the cabin? Mine used to be very discreet - now...not so much. Sounds like it has an aftermarket BOV - very audible.

[xxMike61]

Originally Posted by JJaber

Do you notice your BOV sounding more noticeable from inside the cabin? Mine used to be very discreet - now...not so much. Sounds like it has an aftermarket BOV - very audible.

If we're both talking about n55, they don't have BOV they have Diverter valves. But yeah I installed it with the optional spring and I haven't really noticed it's sound anymore. The old DV released everything at once so maybe that's why it is more noticeable

[Pladi]

Originally Posted by xxMike61

I've had a rattle for a while now and boost was always a 2-3 psi from target all throughout the pull. Installed GFB DV to see if anything helped but I dont see any difference in the logs. I do have stock FMIC connections so that might be it? But the rattle is driving me crazy, I can't drive with my windows down because its so noticeable.

Good to know. I have never found the cause of this 2-3 psi offset and under target. I have seen it with many many peoples logs. Only with ots mhd tunes by twisted tuning. My PPK was alway on target. And all n54 logs i see are on target. I replaced boost solenoid and was gonna do the DV.

[TheGoodTheBadTheUgly]

I recently installed the DV+ from GFB. I didn't take proper logs yet, but I do drive with monitors on. 3 dials, one for IAT, another one for Boost and last one Boost target.

With the DV+ I noticed that I am more over the boost target then before. With stock DV I use to be always lower with some minor exceptions.

I think a hard wastegate rattle could impact the performance of the car, but I don't quite see how it could affect the boost that is building.

EDIT: Scratch that I don't know why I didn't think about this earlier but wastegate can affect boost build. If the wastegate isn't functioning properly and lets out too much exhaust gasses out then the turbine will not achieve its work target which is also the work used by the compressor in order to achieve higher pressure. Sorry about that .

[JJaber]

Originally Posted by TheGoodTheBadTheUgly

I recently installed the DV+ from GFB. I didn't take proper logs yet, but I do drive with monitors on. 3 dials, one for IAT, another one for Boost and last one Boost target.

With the DV+ I noticed that I am more over the boost target then before. With stock DV I use to be always lower with some minor exceptions.

I think a hard wastegate rattle could impact the performance of the car, but I don't quite see how it could affect the boost that is building.

EDIT: Scratch that I don't know why I didn't think about this earlier but wastegate can affect boost build. If the wastegate isn't functioning properly and lets out too much exhaust gasses out then the turbine will not achieve its work target which is also the work used by the compressor in order to achieve higher pressure. Sorry about that .

I'm running a Dinan Stage 2 - I wonder if going back to stock would remedy this (for the time being). Are there any concrete fixes besides replacing the whole unit? My car only has 56k miles (12k running Dinan stage II)

[TheGoodTheBadTheUgly]

Originally Posted by JJaber

I'm running a Dinan Stage 2 - I wonder if going back to stock would remedy this (for the time being). Are there any concrete fixes besides replacing the whole unit? My car only has 56k miles (12k running Dinan stage II)

So I don't know what type of tune is the Dinan, like if it's a piggy back or ECU Flash, but if it's easy to revert back to stock you lose nothing from trying.

With all these years of rolling, the wastegate sometimes gets loose and the mounting points/brackets are the one provoking this rattle. You can try to tighten the wastegate back and see if it fixes it.

If not that probably means that the internals of your wastegates are the one creating the rattle and you would need to replace it.

[JJaber]

Originally Posted by TheGoodTheBadTheUgly

So I don't know what type of tune is the Dinan, like if it's a piggy back or ECU Flash, but if it's easy to revert back to stock you lose nothing from trying.

With all these years of rolling, the wastegate sometimes gets loose and the mounting points/brackets are the one provoking this rattle. You can try to tighten the wastegate back and see if it fixes it.

If not that probably means that the internals of your wastegates are the one creating the rattle and you would need to replace it.

I've just noticed a very BOV-ish "woosh" sound when I let go of the gas now and the rattle is present on acceleration and deceleration - it used to be very quiet. From what I understand, the entire turbine and waste-gate would need to be replaced - in which case I'll probably just sell the car.

[TheGoodTheBadTheUgly]

Originally Posted by JJaber

I've just noticed a very BOV-ish "woosh" sound when I let go of the gas now and the rattle is present on acceleration and deceleration - it used to be very quiet. From what I understand, the entire turbine and waste-gate would need to be replaced - in which case I'll probably just sell the car.

Hmmm the whole turbine? Are you able to log and see what your boost is looking like?
And you are sure that strange sound is more a woosh than a chirping?

[weehe126]

Originally Posted by JJaber

I've just noticed a very BOV-ish "woosh" sound when I let go of the gas now and the rattle is present on acceleration and deceleration - it used to be very quiet. From what I understand, the entire turbine and waste-gate would need to be replaced - in which case I'll probably just sell the car.

I don't think you understand right.

[xxMike61]

Noticed a strange light rattle at idle a week ago maybe but didnt think it was anything. Today I was driving and noticed that when coming to a stop the rpm would dip past 500. The car even died on me on the freeway thankfully it was stand still traffic.

Got home and revved it in park and sounded pretty identical to this. I had been chasing a rattle for probably a year now and always suspected it was the wastegate/flapper or something. Today the car built 4 psi out of the 14 target when I floored it. Doubt it could be any of the FMIC connections. Just did GFB DV so its not that.

Now just wondering if I have to replace whole turbo or if there is just a wastegate part.

[lwgrenier]

Originally Posted by xxMike61

Today I was driving and noticed that when coming to a stop the rpm would dip past 500. The car even died on me on the freeway thankfully it was stand still traffic.

I could be wrong but I wouldn't think a wastegate issue would cause the car to stall.

[xxMike61]

Originally Posted by lwgrenier

I could be wrong but I wouldn't think a wastegate issue would cause the car to stall.

Yeah you're right I think I have a huge boost leak instead. I can hear it

[xxMike61]

Update: found out what the problem was. the plug of the bottom bung on my charge pipe fell out. luckily it was in the belly pan even after 90+ miles. put it back and now have boost again

[DiFFv1]

Originally Posted by xxMike61

Update: found out what the problem was. the plug of the bottom bung on my charge pipe fell out. luckily it was in the belly pan even after 90+ miles. put it back and now have boost again

Good shet, Im glad you solved the issue

[JJaber]

Originally Posted by xxMike61

Update: found out what the problem was. the plug of the bottom bung on my charge pipe fell out. luckily it was in the belly pan even after 90+ miles. put it back and now have boost again

Crazy how that wouldn’t throw a code!

[TheGoodTheBadTheUgly]

Originally Posted by xxMike61

Update: found out what the problem was. the plug of the bottom bung on my charge pipe fell out. luckily it was in the belly pan even after 90+ miles. put it back and now have boost again

Woow that is so weird. I just put screws instead of the plugs. I am very happy to hear it was something simple and not critical.

[xxMike61]

Yeah sorry the "plug" im talking about is the hex bit screw thingy. I installed a friends CP and noticed that his too were kind of loose right out of the box so i tightened his down for him.

I tightened both of mine with a bit of loctite just in case lol

[TheGoodTheBadTheUgly]

Originally Posted by xxMike61

Yeah sorry the "plug" im talking about is the hex bit screw thingy. I installed a friends CP and noticed that his too were kind of loose right out of the box so i tightened his down for him.

I tightened both of mine with a bit of loctite just in case lol

I hope it won't happen anymore, but at least you know another thing to pin point if it ever happens in the future!