Rough Idle back after Techron Cleaner

Amadayus · 09-23-2016, 01:43 PM

I had a rough idle that when the A/C is turned on, it becomes more apparent weeks ago. I then put some Techron Concentrate Plus, thinking maybe the fuel injectors were dirty and were the cause.

The Result after first treatment: The car's rough idle immediately went away with the first tank of gas....However, now on my 3rd tank after Techron, it looks like the Rough Idle is back.

Should I do another Techron Concentrate Plus Treatment? Does the rough idle going away after the first Techron treatment conclude that it is likely a dirty fuel injector problem?

I'm trying to plan ahead if a second treatment does not work and also know that Rough Idle can be from many problems. Please share your any helpful thoughts, thanks!

W37V · 09-23-2016, 06:46 PM

Try another treatment and see if it gets rid of it. If not...

It could be bad plugs(unlikely, but possible ) or bad coil (failing). I would swap them out just as a regular maintenance.

JayTriggy14 · 09-23-2016, 08:49 PM

I would try looking at the spark plugs/coils. If that isn't the case take a look at the vanos coils. That seems to fix the problem for most people. Check out this thread for details.

http://www.e90post.com/forums/showthread.php?t=277195

DominicHustle22 · 09-27-2016, 12:29 PM

Yeah I +1 what the other guys said. Plug in an OBD reader and see if it's throwing any codes.

Three_thirty_I · 09-27-2016, 04:14 PM

If this persists, try and see if there are any irregularities with the Smooth Running parameters - this will pick up any issues with each combustion process for the various cylinders.

Amadayus · 10-01-2016, 01:19 AM

Appreciate the valuable input everyone! I will try another treatment and see if the elimination of the rough idle is sustained. If not, it will be on to the next interventions as suggested.

F22_Raptor · 10-01-2016, 04:36 AM

Check your eccentric shaft sensor.

gbm30 · 10-01-2016, 08:25 AM

Check the vacuum hose near the back of the engine. Make sure jus not brittle or have any oil on it. The check your spark plugs and ignition pack. If not run a scan or get a smoke test.

09-23-2016, 01:43 PM	#1
Amadayus Enlisted Member 5 Rep 31 Posts Drives: F32, G01 X3 M40i Join Date: May 2010 Location: Los Angeles iTrader: (1)	Rough Idle back after Techron Cleaner I had a rough idle that when the A/C is turned on, it becomes more apparent weeks ago. I then put some Techron Concentrate Plus, thinking maybe the fuel injectors were dirty and were the cause. The Result after first treatment: The car's rough idle immediately went away with the first tank of gas....However, now on my 3rd tank after Techron, it looks like the Rough Idle is back. Should I do another Techron Concentrate Plus Treatment? Does the rough idle going away after the first Techron treatment conclude that it is likely a dirty fuel injector problem? I'm trying to plan ahead if a second treatment does not work and also know that Rough Idle can be from many problems. Please share your any helpful thoughts, thanks! Last edited by Amadayus; 09-23-2016 at 05:47 PM..
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09-23-2016, 06:46 PM	#2
W37V [Oo=\|\|=oO] 1125 Rep 2,470 Posts Drives: e92n52 & f15n57 Join Date: Aug 2014 Location: DMV iTrader: (0)	Try another treatment and see if it gets rid of it. If not... It could be bad plugs(unlikely, but possible ) or bad coil (failing). I would swap them out just as a regular maintenance.
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09-23-2016, 08:49 PM	#3
JayTriggy14 Associate Special Class 30 Rep 105 Posts Drives: 2013 335is Join Date: Aug 2016 Location: San Diego, CA iTrader: (0) Garage List 2013 BMW 335is [10.00]	I would try looking at the spark plugs/coils. If that isn't the case take a look at the vanos coils. That seems to fix the problem for most people. Check out this thread for details. http://www.e90post.com/forums/showthread.php?t=277195 __________________ 2013 E92 Alpine White 335is: 7spd DCT
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09-27-2016, 12:29 PM	#4
DominicHustle22 Private 3 Rep 89 Posts Drives: 2006 325xi Join Date: Jul 2015 Location: New York iTrader: (0)	Yeah I +1 what the other guys said. Plug in an OBD reader and see if it's throwing any codes. __________________ Gruppe M Ram Air Intake \| Active Autowerke Signature Exhaust \| AA Stage 2 Tune \| Koni FSDs \| Eibach Pro-Kit \| Dinan Camber Plates \| Hamann CF Front Lip Rep \| BMW CF Performance Spoiler Rep \| ECS Intake Scoops \| CF Roundels \| 19x8" TSW Nurburgrings \| 245/35 Michelin Pilot AS3 \| VRSF Spacers F10/R18mm \| LUX Angel Eyes \| M Smoked LED Side Markers \| Performance Lever + Leather Boot \| M Perforated E-Brake
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09-27-2016, 04:14 PM	#5
Three_thirty_I Lieutenant Colonel 350 Rep 1,915 Posts Drives: 2010 BMW E90 330i M Sport Join Date: Aug 2010 Location: Cape Town, South Africa iTrader: (0) Garage List 2010 BMW E90 330i M ... [9.63]	If this persists, try and see if there are any irregularities with the Smooth Running parameters - this will pick up any issues with each combustion process for the various cylinders. __________________ 2010 BMW E90 330i M Sport (M) Ex: BMW E90 330i (M) '05 (His) \| (Hers) BMW E46 320i f/l (M) '03
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10-01-2016, 01:19 AM	#6
Amadayus Enlisted Member 5 Rep 31 Posts Drives: F32, G01 X3 M40i Join Date: May 2010 Location: Los Angeles iTrader: (1)	Appreciate the valuable input everyone! I will try another treatment and see if the elimination of the rough idle is sustained. If not, it will be on to the next interventions as suggested.
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10-01-2016, 04:36 AM	#7
F22_Raptor Lieutenant 115 Rep 424 Posts Drives: 2008 328i Join Date: Aug 2015 Location: Touring CA iTrader: (0)	Check your eccentric shaft sensor. __________________
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10-01-2016, 08:25 AM	#8
gbm30 Private 24 Rep 76 Posts Drives: bmw e90 330i Join Date: May 2013 Location: new york iTrader: (0)	Check the vacuum hose near the back of the engine. Make sure jus not brittle or have any oil on it. The check your spark plugs and ignition pack. If not run a scan or get a smoke test.
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