Uneven idle and lag in acceleration

davitd · 07-22-2011, 09:22 PM

Hi everyone, I have recently done valve cover gasket replacement on my BMW 325 E90. Since then the car behaves strangely - there is a carbon build-up on exhaust pipes, idle is jumping by 50 RPM and sometimes there is a lag when I am trying to accelerate from low RPM, as if there is an interruption in gas supply or something like that. I have talked to BMW dealers and they said about jumping idle that the tacho is too sensitive and there is nothing wrong with it, that I find nonsense, they could not replicate other problems. I live in Georgia, Tbilisi, so there is only one BMW dealer in the country.

krnboy817 · 07-23-2011, 11:27 AM

check out the couple of threads above this one... the ones about ticking noise and rough idle...

i think youll find those handy since its kind of related to this issue.

e90pilot · 07-23-2011, 12:25 PM

You might have broken the PCV line that connects to the back valve cover. I have a thread on this it's gonna be near this one.

Edit: this - http://www.e90post.com/forums/showthread.php?t=561939

BigDog · 07-25-2011, 03:14 PM

vanos solenoid issue here.... apparently its a common replacement part once you get the miles up there

davitd · 07-26-2011, 02:57 PM

Well, I have had my car scanned and there are no errors at all. I have changed spark plugs and checked the vacuum of the inlet and the whole engine. No leaks at all. Nobody can tell me what is wrong with it.

davitd · 07-27-2011, 12:21 AM

I have noticed that the probleb is associated with outside air temperature. With high ambiant temperatures the car jerks ant 1300-1800 RPM. Could it be associated with injectors or fuel pump. It still does not throw any codes

07-22-2011, 09:22 PM	#1
davitd Enlisted Member 9 Rep 34 Posts Drives: bmw 325 e90 Join Date: Jul 2011 Location: Georgia iTrader: (0)	Uneven idle and lag in acceleration Hi everyone, I have recently done valve cover gasket replacement on my BMW 325 E90. Since then the car behaves strangely - there is a carbon build-up on exhaust pipes, idle is jumping by 50 RPM and sometimes there is a lag when I am trying to accelerate from low RPM, as if there is an interruption in gas supply or something like that. I have talked to BMW dealers and they said about jumping idle that the tacho is too sensitive and there is nothing wrong with it, that I find nonsense, they could not replicate other problems. I live in Georgia, Tbilisi, so there is only one BMW dealer in the country.
	Appreciate 0 Tweet Quote

07-23-2011, 11:27 AM	#2
krnboy817 Major 44 Rep 1,011 Posts Drives: 2008 328i coupe Join Date: Oct 2010 Location: DFW texas iTrader: (3)	check out the couple of threads above this one... the ones about ticking noise and rough idle... i think youll find those handy since its kind of related to this issue. __________________ driving is poetry in motion.
	Appreciate 0 Quote

07-23-2011, 12:25 PM	#3
e90pilot Freight Dawg 104 Rep 2,103 Posts Drives: E90 325i Join Date: Jul 2005 Location: Oakland, CA iTrader: (3)	You might have broken the PCV line that connects to the back valve cover. I have a thread on this it's gonna be near this one. Edit: this - http://www.e90post.com/forums/showthread.php?t=561939 __________________ --Marcelo '06 Arctic Metallic 325i \| Sport Package \| 6MT \| Dinan Stage III suspension \| Dinan exhaust \| 330i manifold swap! Click here! \| Active Autowerke tune \| 135i Brake Calipers \| Deiselboost caliper brackets \| E46 M3 front rotors Last edited by e90pilot; 07-23-2011 at 06:38 PM..
	Appreciate 0 Quote

07-25-2011, 03:14 PM	#4
BigDog Major 323 Rep 1,080 Posts Drives: YMB F80 Join Date: Jul 2005 Location: NYC iTrader: (1)	vanos solenoid issue here.... apparently its a common replacement part once you get the miles up there __________________
	Appreciate 0 Quote

07-26-2011, 02:57 PM	#5
davitd Enlisted Member 9 Rep 34 Posts Drives: bmw 325 e90 Join Date: Jul 2011 Location: Georgia iTrader: (0)	Well, I have had my car scanned and there are no errors at all. I have changed spark plugs and checked the vacuum of the inlet and the whole engine. No leaks at all. Nobody can tell me what is wrong with it.
	Appreciate 0 Quote

07-27-2011, 12:21 AM	#6
davitd Enlisted Member 9 Rep 34 Posts Drives: bmw 325 e90 Join Date: Jul 2011 Location: Georgia iTrader: (0)	I have noticed that the probleb is associated with outside air temperature. With high ambiant temperatures the car jerks ant 1300-1800 RPM. Could it be associated with injectors or fuel pump. It still does not throw any codes
	Appreciate 0 Quote