Random idle problems.

BurrNinja · 09-07-2016, 10:48 PM

I recently purchased this 2008 328i from yark. I've been noticing problems with the AC turned on the car would act as if it had a loss of power for a split second go back to normal and repeat sometimes. I replaced the old spark plugs with new ngk iridium ones. Done oil change, mind you the oil looked as if it was boarder line needed done. I cleaned the throttle body out, had some carbon build up on it. One of the coils looked as if were replaced when I did my spark plugs. Also cleaned out my MAF. No codes shown either. Just wondering why would the AC on MAX make the idle drop 50 rpm like it had a loss of power? Any suggestions? Also, i noticed one of the coils had a sealant on the top of it near the clip and it looked a lot different then the other 5. Im gonna replace that one to see if anything changes.

BurrNinja · 09-09-2016, 04:57 PM

Update, as I was in traffic just after work 85°f outside. The surge/jerk got more constant. The fan would kick on to cool my engine, and the surge would start in more and more constant. I tried testing out while in park, it still did it.

Tom Droze · 09-09-2016, 06:00 PM

Is your idle only erratic with the AC on?

VTECaddict · 09-09-2016, 11:01 PM

I've had this on and off a few times. Most likely it's the coils. It's hard to track down which coil because it's bad enough to cause that slight hiccup/misfire, but not bad enough to cause a misfire code.

You can replace them all at once or just get one new one and move it from cylinder to cylinder until it stops doing it.

BurrNinja · 09-10-2016, 05:34 PM

Its worse with the AC on, specially on a hot day im talking 80+ degrees. Heres a small video of what happens when stopped at a light break on in drive. The rpm fluctuation starts at 11 seconds its a slight drop and raise but it seems like it chokes hard.

Stupenal · 09-11-2016, 01:08 AM

I had this issue with the random stumbling idle but it would happen with it without AC on. Idle would stumble and dip then come back, everything else was fine when driving though.

I knew my vcg was leaking. Replaced the vcg plus valve tronic gasket plus eccentric shaft sensor gasket and used electrical contact cleaner where the sensor plugs in. Stumble gone and idle is perfect.

BurrNinja · 09-11-2016, 04:50 PM

I didn't notice any oil leakage when replacing the spark plugs. If the oil even got to it if it was bad. One thing i did notice i did a quick pull apart to get to the ignition coils, 5 of them are bosch oem, the other one was a delphi not sure if that has anything to do with it. Not to mention when i seen the delphi coil it had this weird yellowish hardened stuff like in the picture shown, not sure if it has anything to do with it.

TrAcK TRaP · 09-11-2016, 05:16 PM

Quote:

Originally Posted by blackwidow328i

I didn't notice any oil leakage when replacing the spark plugs. If the oil even got to it if it was bad. One thing i did notice i did a quick pull apart to get to the ignition coils, 5 of them are bosch oem, the other one was a delphi not sure if that has anything to do with it. Not to mention when i seen the delphi coil it had this weird yellowish hardened stuff like in the picture shown, not sure if it has anything to do with it.

You shouldn't mix bosch and delphi coils. Thats your problem..

BurrNinja · 09-11-2016, 06:21 PM

Ok, another question when does inter cooler fan kick on like what temp? I noticed mine was on high or at least sounded as if at 99 Degrees Celsius. But i will order a whole set of delphi after hearing they are good, i will replace them and post my update or should i go with bosch a whole set verse delphi?

Phil325i · 09-12-2016, 10:45 AM

In Europe at least, Dlephi has replaced Bosch as manufacturer of BMW coils. New part number and revised design and incorporating a metal sleeve (heat shield?) as shown in your pic.

BurrNinja · 09-12-2016, 04:29 PM

The stupid thing i dont get, why would my car not act up like in the video on a cooler day? Only when its blistering 85+ out is when it acts rough as hell.

BurrNinja · 09-14-2016, 01:38 PM

Just ordered a set of delphi one day shipping, will post results soon as i get installed.

BurrNinja · 09-15-2016, 05:43 PM

Just got the set in, took no less then 20 minutes. Easy install, seems to run more smoothly. Gonna post results "if" and "when" it gets blistering hot one day... Only thing i find sketchy about the new coils is that the seem to be able to twist easily but they are locked down.

Arby1028 · 11-13-2016, 09:57 AM

Any updates on this? I'm having a similar problem but the surge is happening under 10mph and when turning or going into reverse.

ny325 · 11-22-2016, 11:56 PM

Funny thing is, my RPMs jump up and down when temperatures drop. Usually around 30-40 degrees.

BurrNinja · 12-22-2016, 02:27 AM

So far is good, replaced all coils. Sorry for late post.

09-07-2016, 10:48 PM	#1
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	Random idle problems. I recently purchased this 2008 328i from yark. I've been noticing problems with the AC turned on the car would act as if it had a loss of power for a split second go back to normal and repeat sometimes. I replaced the old spark plugs with new ngk iridium ones. Done oil change, mind you the oil looked as if it was boarder line needed done. I cleaned the throttle body out, had some carbon build up on it. One of the coils looked as if were replaced when I did my spark plugs. Also cleaned out my MAF. No codes shown either. Just wondering why would the AC on MAX make the idle drop 50 rpm like it had a loss of power? Any suggestions? Also, i noticed one of the coils had a sealant on the top of it near the clip and it looked a lot different then the other 5. Im gonna replace that one to see if anything changes. Last edited by BurrNinja; 09-07-2016 at 11:05 PM..
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09-09-2016, 04:57 PM	#2
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	Update, as I was in traffic just after work 85°f outside. The surge/jerk got more constant. The fan would kick on to cool my engine, and the surge would start in more and more constant. I tried testing out while in park, it still did it.
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09-09-2016, 06:00 PM	#3
Tom Droze Major 413 Rep 1,286 Posts Drives: 2012 BMW 328i (e92) Join Date: Jul 2014 Location: Scottsdale, Arizona iTrader: (0)	Is your idle only erratic with the AC on? __________________ 2012 Jet Black 328i Coupe / ESS Tuning Gen. 2 Supercharger / Evolution Racewerks Oil Cooler / BMS Oil Catch Can / BMW Performance Exhaust with Dinan Y Pipe / Eibach Pro Kit Springs / Koni FSD Shocks / MFactory LSD & Differential Bushings / Performance Rear Trailing Arms / BMW Performance Strut Brace / Stop Tech Slotted Rotors / Hawk HPS 5.0 / SS Brake Lines / Brass Guide Pins / M3 Front Control Arms, 28 MM FSB, Engine Cowl, and DCT Paddle Shifters / Michelin PSS / APEX ARC-8
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09-09-2016, 11:01 PM	#4
VTECaddict Where'd my VTEC go? 487 Rep 6,066 Posts Drives: 06 330i 6MT Join Date: Mar 2009 Location: Seattle, WA iTrader: (4)	I've had this on and off a few times. Most likely it's the coils. It's hard to track down which coil because it's bad enough to cause that slight hiccup/misfire, but not bad enough to cause a misfire code. You can replace them all at once or just get one new one and move it from cylinder to cylinder until it stops doing it. __________________ AW/Terra \| ZSP \| ZPP \| ZCW \| iDrive \| CA Mods: BC BR coilovers \| Blacklines \| M-tech rear \| dual exhaust \| M3 steering wheel \| BMW SSK \| ZHP shift knob \| High-kick CF spoiler \| NBT Retrofit M3 front control arms \| M3 rear guide rods \| Manzo rear toe and camber links \| Monroe rear shock mounts \| Varrstoen ES1 19x9.5+20 Front, 19x11+25 rear
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09-10-2016, 05:34 PM	#5
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	Its worse with the AC on, specially on a hot day im talking 80+ degrees. Heres a small video of what happens when stopped at a light break on in drive. The rpm fluctuation starts at 11 seconds its a slight drop and raise but it seems like it chokes hard. Last edited by BurrNinja; 09-10-2016 at 05:40 PM..
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09-11-2016, 01:08 AM	#6
Stupenal First Lieutenant 46 Rep 347 Posts Drives: Mmm Join Date: May 2009 Location: Socal iTrader: (10)	I had this issue with the random stumbling idle but it would happen with it without AC on. Idle would stumble and dip then come back, everything else was fine when driving though. I knew my vcg was leaking. Replaced the vcg plus valve tronic gasket plus eccentric shaft sensor gasket and used electrical contact cleaner where the sensor plugs in. Stumble gone and idle is perfect.
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09-11-2016, 04:50 PM	#7
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	I didn't notice any oil leakage when replacing the spark plugs. If the oil even got to it if it was bad. One thing i did notice i did a quick pull apart to get to the ignition coils, 5 of them are bosch oem, the other one was a delphi not sure if that has anything to do with it. Not to mention when i seen the delphi coil it had this weird yellowish hardened stuff like in the picture shown, not sure if it has anything to do with it.
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09-11-2016, 06:21 PM	#9
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	Ok, another question when does inter cooler fan kick on like what temp? I noticed mine was on high or at least sounded as if at 99 Degrees Celsius. But i will order a whole set of delphi after hearing they are good, i will replace them and post my update or should i go with bosch a whole set verse delphi?
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09-12-2016, 10:45 AM	#10
Phil325i Brigadier General 639 Rep 3,217 Posts Drives: E92 325i MSport Coupe Join Date: Apr 2012 Location: UK South East iTrader: (1) Garage List 2009 BMW 325i Coupe [6.00]	In Europe at least, Dlephi has replaced Bosch as manufacturer of BMW coils. New part number and revised design and incorporating a metal sleeve (heat shield?) as shown in your pic. __________________ E92 pre-LCI 325i - Ohlins R&T; H&R spacers; M3 strut brace; Swift thrust sheets; 3 x chassis braces; diff brace; N53 V-brace; 034 subframe inserts; BMS clutch stop; BMS CDV; RE g/box mounts; Delrin shift bushes; Saikoumichi OCC; Cyba scoops; BMW Perf Exhaust; HEL s/steel brake hoses; M3 rear spoiler; Recaro Sportster CSs; M3 white dash LEDs; LED Angels; LED side repeaters; BMW Perf black grille; CSL reps; SSDD carbon diffuser; Monster Wrap black roof/clear front
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09-12-2016, 04:29 PM	#11
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	The stupid thing i dont get, why would my car not act up like in the video on a cooler day? Only when its blistering 85+ out is when it acts rough as hell.
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09-14-2016, 01:38 PM	#12
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	Just ordered a set of delphi one day shipping, will post results soon as i get installed.
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09-15-2016, 05:43 PM	#13
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	Just got the set in, took no less then 20 minutes. Easy install, seems to run more smoothly. Gonna post results "if" and "when" it gets blistering hot one day... Only thing i find sketchy about the new coils is that the seem to be able to twist easily but they are locked down.
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11-13-2016, 09:57 AM	#14
Arby1028 Private First Class 10 Rep 103 Posts Drives: 2011 BMW 335i Sedan (e90) Join Date: Oct 2016 Location: North Carolina iTrader: (0)	Any updates on this? I'm having a similar problem but the surge is happening under 10mph and when turning or going into reverse.
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11-22-2016, 11:56 PM	#15
ny325 Brigadier General 898 Rep 3,140 Posts Drives: Jet Black E90 Join Date: Feb 2007 Location: Gridlock iTrader: (0)	Funny thing is, my RPMs jump up and down when temperatures drop. Usually around 30-40 degrees.
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12-22-2016, 02:27 AM	#16
BurrNinja Captain 443 Rep 921 Posts Drives: 2017 540i Bluestone Metallic Join Date: Jul 2016 Location: Ohio iTrader: (0) Garage List 2017 Bmw 540i [10.00]	So far is good, replaced all coils. Sorry for late post.
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