BMW X3 Forum
BMW X3 Forum
Welcome to the ultimate BMW X3 community.
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
Post Reply
 
Thread Tools Search this Thread
      12-08-2018, 02:52 PM   #1
Deliberate2
Private
26
Rep
92
Posts

Drives: '72 2002 (RIP)
Join Date: Oct 2018
Location: Maine

iTrader: (0)

Engine hesitation under load

Friends, my wife drives an '11 35i with 111,000 miles. The car just developed what feels like a subtle hesitation under load. There appears to be no discernible loss of power. And, again, only happens on harder acceleration, not when coasting or low acceleration, and is not constant. Just had the water pump and thermostat replaced. When we did the shop suggested replacing the plugs - but as a maintenance issue, indicating that the replacement should be done at 60k.
Diagnostic thoughts? Much obliged.
Appreciate 0
      12-08-2018, 03:07 PM   #2
Wgosma
Lieutenant Colonel
United_States
800
Rep
1,895
Posts

Drives: 2012 F25 X3 28i (N52)
Join Date: Sep 2018
Location: Northern Nevada

iTrader: (0)

I've read that some of these 'direct fuel injection' motors can be subject to carbon buildup on the intake valves...think this occurs when mileage gets in the range where you're at.

You might run that past your mechanic and get his thoughts. The remedy if this is the issue is to walnut blast the intake valves- believe it requires removing intake manifold, so not exactly a minor kind of procedure.

I'm sure others on the forum may have addl ideas as to your car's behavior.
Good luck/Bill
Appreciate 0
      12-08-2018, 03:39 PM   #3
Deliberate2
Private
26
Rep
92
Posts

Drives: '72 2002 (RIP)
Join Date: Oct 2018
Location: Maine

iTrader: (0)

Quote:
Originally Posted by Wgosma View Post
I've read that some of these 'direct fuel injection' motors can be subject to carbon buildup on the intake valves...think this occurs when mileage gets in the range where you're at.

You might run that past your mechanic and get his thoughts. The remedy if this is the issue is to walnut blast the intake valves- believe it requires removing intake manifold, so not exactly a minor kind of procedure.

I'm sure others on the forum may have addl ideas as to your car's behavior.
Good luck/Bill
Bill, thanks for the suggestion. Is this the sort of malady that can be detected by electronic diagnostic testing or is it an eyeball or "informed" guess thing?
Cheers,
David
Appreciate 0
      12-08-2018, 04:13 PM   #4
E90705
First Lieutenant
E90705's Avatar
United_States
127
Rep
383
Posts

Drives: E90/F25 M-sport
Join Date: Mar 2015
Location: Central

iTrader: (0)

Hook it up to a diagnostic tool and scan for any dme codes.
Appreciate 0
      12-08-2018, 04:33 PM   #5
Wgosma
Lieutenant Colonel
United_States
800
Rep
1,895
Posts

Drives: 2012 F25 X3 28i (N52)
Join Date: Sep 2018
Location: Northern Nevada

iTrader: (0)

Quote:
Originally Posted by E90705 View Post
Hook it up to a diagnostic tool and scan for any dme codes.
+1....diagnostics!

Carbon buildup: my sense would be that if you're seeing a misfire code, slightly rough running AND all other possibilities (faulty coil packs, fuel injector/pump, etc.) are ruled OUT then the intake valves may be at issue.

I'm not a mechanic, you need a competent trusty one!
Bill
Appreciate 0
      12-08-2018, 04:49 PM   #6
Deliberate2
Private
26
Rep
92
Posts

Drives: '72 2002 (RIP)
Join Date: Oct 2018
Location: Maine

iTrader: (0)

Thanks, gents.
Just when I thought I was done spending on this car, for the moment....
Off to the dealer.
David
Appreciate 0
      12-08-2018, 07:05 PM   #7
________
________
4157
Rep
2,301
Posts

Drives: ________
Join Date: Sep 2018
Location: ________

iTrader: (0)

Mine developed that, it was a dirty air filter. I'd start there if you haven't already.
Appreciate 0
      12-08-2018, 09:29 PM   #8
BIG_KID
Second Lieutenant
BIG_KID's Avatar
67
Rep
285
Posts

Drives: 2011 X3 28i
Join Date: Dec 2017
Location: Northern indiana

iTrader: (0)

Quote:
Originally Posted by OnerDriver View Post
Mine developed that, it was a dirty air filter. I'd start there if you haven't already.
I would start with the small stuff like this first. Possibly dirty MAF, plugs, coils, etc.
Appreciate 0
      12-09-2018, 08:44 AM   #9
Deliberate2
Private
26
Rep
92
Posts

Drives: '72 2002 (RIP)
Join Date: Oct 2018
Location: Maine

iTrader: (0)

Quote:
Originally Posted by BIG_KID View Post
I would start with the small stuff like this first. Possibly dirty MAF, plugs, coils, etc.
Will do.
Cheers.
Appreciate 0
      12-09-2018, 10:49 AM   #10
tracer bullet
Brigadier General
tracer bullet's Avatar
United_States
2291
Rep
3,463
Posts

Drives: '11 135i , '15 X3 35i
Join Date: May 2011
Location: Saint Paul, MN

iTrader: (1)

I could believe plugs as well, at the mileage it is indeed time for them. In previous cars I've owned over ~ 30 years this sort of behavior stumbling when accelerating was typically the plugs / wires / or distributor cap & rotor, 2 of the 3 which aren't of course on an X3 leaving just the 1 left for where I'd start. The air filter idea is solid as well if you aren't sure the last time it was replaced. That for sure is an easy DIY.

This is the one I put into mine, but it was a 2015 35i and your older one may be different, check to be sure.

https://www.amazon.com/Mann-Filter-2...ype=automotive
Appreciate 0
      12-11-2018, 12:36 PM   #11
Deliberate2
Private
26
Rep
92
Posts

Drives: '72 2002 (RIP)
Join Date: Oct 2018
Location: Maine

iTrader: (0)

Quote:
Originally Posted by tracer bullet View Post
I could believe plugs as well, at the mileage it is indeed time for them. In previous cars I've owned over ~ 30 years this sort of behavior stumbling when accelerating was typically the plugs / wires / or distributor cap & rotor, 2 of the 3 which aren't of course on an X3 leaving just the 1 left for where I'd start. The air filter idea is solid as well if you aren't sure the last time it was replaced. That for sure is an easy DIY.

This is the one I put into mine, but it was a 2015 35i and your older one may be different, check to be sure.

https://www.amazon.com/Mann-Filter-2...ype=automotive
On order. Obliged for the suggestion.
Appreciate 0
      12-12-2018, 12:47 PM   #12
najnad
General of the Space Forces
najnad's Avatar
United_States
171
Rep
721
Posts

Drives: 11 X3 35i M-sport
Join Date: May 2012
Location: Elkridge, MD

iTrader: (0)

Garage List
What RPM is it happening at? I had a similar problem, turned out to be a bad spark plug. Was happening under load just under 2000 RPM.
__________________
Current: 2020 X5 x40i M-Sport, Arctic Grey Metallic / Ivory White, Executive Package, Luggage Compartment Package, Integral Active Steering, Tow Package, Parking Assist Package, Driving Assist Package, M-Sport brakes, Tux Mats
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 05:15 PM.




xbimmers
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST