surging at low rpms. Could VANOS be involved

sipman · 09-14-2012, 07:18 PM

Hi,
I find that when I'm driving around town, I give it some gas to accelerate moderately, which the car does.
Suddenly, it develops way more power. This occurs at lower rpms, maybe 2 or 3000 rpm.

I noticed this after installing the e46 M3 K&N cold air kit. I don't know if it's a coincidence that I noticed it after the install, and I'm not sure why this would cause problems. I mean, it's the same engine in both cars, so even though I'm using the M3 specific intake in the Z4, I'm not convinced that this could be the cause.

Car has 20,000 miles on it, so I've got to do the valves soon. But I'm suddenly worried that the surge might be VANOS related. Anyone with a similar experience?

Caddyshk · 09-14-2012, 08:38 PM

Put the stock air box back on and see. Thought I read somewhere the K & N intake actually reduces performance on the S54?

Finnegan · 09-14-2012, 09:16 PM

^WHS

And check the MAF. Sounds like something MAF related, but like Caddy said it's probably secondary to the airbox. It is the same engine, but different ECU, and other differences as well.

09-14-2012, 07:18 PM	#1
sipman Private First Class 19 Rep 196 Posts Drives: 2007 Z4MC Join Date: Jan 2010 Location: Philly iTrader: (1)	surging at low rpms. Could VANOS be involved Hi, I find that when I'm driving around town, I give it some gas to accelerate moderately, which the car does. Suddenly, it develops way more power. This occurs at lower rpms, maybe 2 or 3000 rpm. I noticed this after installing the e46 M3 K&N cold air kit. I don't know if it's a coincidence that I noticed it after the install, and I'm not sure why this would cause problems. I mean, it's the same engine in both cars, so even though I'm using the M3 specific intake in the Z4, I'm not convinced that this could be the cause. Car has 20,000 miles on it, so I've got to do the valves soon. But I'm suddenly worried that the surge might be VANOS related. Anyone with a similar experience? __________________
	Appreciate 0 Tweet Quote

09-14-2012, 08:38 PM	#2
Caddyshk M = Midlife Crisis 65 Rep 2,006 Posts Drives: 2006 Z4MC Interlagos Join Date: May 2007 Location: Fort Erie, Ontario, Canada iTrader: (0)	Put the stock air box back on and see. Thought I read somewhere the K & N intake actually reduces performance on the S54? __________________ 2006 Z4MC - #LL93158 SS Race Cans, RE X Pipe, DKF Sec 1, Fabspeed Headers, OE STB, AS Shifter, Dave Z CDV, GC Coil Overs, Stoptech lines, Hawk DTC Pads, RE Clutch Stop, RE Transmission Mounts, Vibra-Technics Engine Mounts, Poly FCAB & RTAB, LeatherZ M Shift Boot, Tekarbon Rear Spoiler, CF Grills, Advan RS DGM
	Appreciate 0 Quote

09-14-2012, 09:16 PM	#3
Finnegan Dog Listener 701 Rep 7,850 Posts Drives: Z4M/. Z3M, E36/46 M3 Join Date: Oct 2008 Location: Teaching the dog to slalom iTrader: (22)	^WHS And check the MAF. Sounds like something MAF related, but like Caddy said it's probably secondary to the airbox. It is the same engine, but different ECU, and other differences as well.
	Appreciate 0 Quote

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search