No boost before 3000k rpms

335dzlll · 10-26-2023, 07:18 PM

I've ran into an issue recently, my car is a 335d with 108k. Before 3k rpms I am seeing no boost or torque but after 3k it goes like it should.

I have no CEL and I've recently replaced my MAP, red charge pipe, turbo inlet seal, all the vacuum lines and checked everything vacuum related on this car and all holds pressure.

One more thing, before replacing my MAP if I started driving the car after letting it sit, it would boost like it should in the lower rpms for about a second or 2 and then proceed to go into limp mode with the power reduced message on the screen but still not putting on a CEL.

The car is deadstock with no deletes besides the swirl flaps(motor is still plugged in). I bought the car in such condition before doing any of the maintenance listed above.

If this helps my EGR pipe that goes to the intercooler looks like it might be leaking and my intercooler fins dented in some spots but nothing major but on the other hand there was a bunch of what to me looked like oil and dirt residue all around where it is mounted on to the bumper. Lastly I don't think my manifold was ever cleaned from carbon buildup as it has a good amount of it.

Thanks for reading any info would greatly help.

BB_cuda · 10-27-2023, 09:12 AM

You didn't mention that you scanned for codes. Just because there in no check engine light doesn't mean a ghost code might be there hinting of what's brewing.

Since you say this happened right after vacuum lines, I would double check your routing is all good. No small turbo running is what it sounds like to me. Check pressure converter if you see a code. Hopefully, you didn't break a nipple off one of them. Good luck.

335dzlll · 10-30-2023, 04:55 PM

I did scan for codes after and there is nothing related to under boost only codes for the fill level sensor for the DEF tank, and glow plug 1,2,3,5 activation codes which I find weird as I've recently replaced all glow plugs and module.

maryjane · 10-30-2023, 07:23 PM

PM me....where in WA are you?

lnxguy · 10-31-2023, 08:34 AM

Sounds like a vac line or pressure convertor issue. When you start the car does the big aluminum can attached to the switchover valve retract? It should.

335dzlll · 10-31-2023, 03:04 PM

I've came to that conclusion as well just haven't got a chance to test it

When doing the vacuum lines I tested it with a vacuum gauge it and the rod moved up and down

In short I did step by step everything this guy did in this video

lnxguy · 10-31-2023, 03:28 PM

It should retract when the car is started. If not, you've found your problem.

335dzlll · 10-31-2023, 06:55 PM

Will do asap and come back with an answer

335dzlll · 11-01-2023, 10:21 PM

The rod moves up when the car is started up.

BB_cuda · 11-02-2023, 11:48 AM

Post #6 shows link to youtube video from our friend yozh.

335dzlll · 11-04-2023, 04:02 PM

im not too knowledgeable on forums .

335dzlll · 12-17-2023, 09:38 PM

Update

i've tested with a new maf -no changes
I replaced a faulty actuator, specifically the closest one to the firewall as it was only out-putting 7 psi(mercury) to a vacuum pump unlike its new replacemnt which sits above 25psi. still sluggish acceleration and almost instant( within 30 feet from the starting place, engine malfunction, drive careful balah blah) but the power in the top end is still there.

10-26-2023, 07:18 PM	#1
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	No boost before 3000k rpms I've ran into an issue recently, my car is a 335d with 108k. Before 3k rpms I am seeing no boost or torque but after 3k it goes like it should. I have no CEL and I've recently replaced my MAP, red charge pipe, turbo inlet seal, all the vacuum lines and checked everything vacuum related on this car and all holds pressure. One more thing, before replacing my MAP if I started driving the car after letting it sit, it would boost like it should in the lower rpms for about a second or 2 and then proceed to go into limp mode with the power reduced message on the screen but still not putting on a CEL. The car is deadstock with no deletes besides the swirl flaps(motor is still plugged in). I bought the car in such condition before doing any of the maintenance listed above. If this helps my EGR pipe that goes to the intercooler looks like it might be leaking and my intercooler fins dented in some spots but nothing major but on the other hand there was a bunch of what to me looked like oil and dirt residue all around where it is mounted on to the bumper. Lastly I don't think my manifold was ever cleaned from carbon buildup as it has a good amount of it. Thanks for reading any info would greatly help.
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10-27-2023, 09:12 AM	#2
BB_cuda Brigadier General 769 Rep 3,555 Posts Drives: 2011 335D Msport, 2013 X5D Join Date: Nov 2011 Location: Clear Lake, Texas iTrader: (0)	You didn't mention that you scanned for codes. Just because there in no check engine light doesn't mean a ghost code might be there hinting of what's brewing. Since you say this happened right after vacuum lines, I would double check your routing is all good. No small turbo running is what it sounds like to me. Check pressure converter if you see a code. Hopefully, you didn't break a nipple off one of them. Good luck.
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10-30-2023, 04:55 PM	#3
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	I did scan for codes after and there is nothing related to under boost only codes for the fill level sensor for the DEF tank, and glow plug 1,2,3,5 activation codes which I find weird as I've recently replaced all glow plugs and module.
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10-30-2023, 07:23 PM	#4
maryjane Second Lieutenant 95 Rep 294 Posts Drives: 2011 335d Msport 3 Snail. Join Date: Mar 2020 Location: GA iTrader: (0)	boost PM me....where in WA are you?
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10-31-2023, 08:34 AM	#5
lnxguy Lieutenant Colonel 358 Rep 1,736 Posts Drives: 2009 335D Join Date: Jun 2016 Location: Barrie iTrader: (1)	Sounds like a vac line or pressure convertor issue. When you start the car does the big aluminum can attached to the switchover valve retract? It should. __________________ '09 335D
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10-31-2023, 03:04 PM	#6
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	I've came to that conclusion as well just haven't got a chance to test it When doing the vacuum lines I tested it with a vacuum gauge it and the rod moved up and down In short I did step by step everything this guy did in this video
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10-31-2023, 03:28 PM	#7
lnxguy Lieutenant Colonel 358 Rep 1,736 Posts Drives: 2009 335D Join Date: Jun 2016 Location: Barrie iTrader: (1)	It should retract when the car is started. If not, you've found your problem. __________________ '09 335D
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10-31-2023, 06:55 PM	#8
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	Will do asap and come back with an answer
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11-01-2023, 10:21 PM	#9
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	The rod moves up when the car is started up.
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11-02-2023, 11:48 AM	#10
BB_cuda Brigadier General 769 Rep 3,555 Posts Drives: 2011 335D Msport, 2013 X5D Join Date: Nov 2011 Location: Clear Lake, Texas iTrader: (0)	Post #6 shows link to youtube video from our friend yozh.
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11-04-2023, 04:02 PM	#11
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	Where do i find that im not too knowledgeable on forums .
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12-17-2023, 09:38 PM	#12
335dzlll New Member 2 Rep 15 Posts Drives: 2009 BMW 335d Join Date: Oct 2023 Location: WA iTrader: (0)	Update i've tested with a new maf -no changes I replaced a faulty actuator, specifically the closest one to the firewall as it was only out-putting 7 psi(mercury) to a vacuum pump unlike its new replacemnt which sits above 25psi. still sluggish acceleration and almost instant( within 30 feet from the starting place, engine malfunction, drive careful balah blah) but the power in the top end is still there.
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