Service lights, myth or fact.

UK forum for general and technical discussion about the Z3 roadster
Post Reply
broony
Joined: Mon 23 Jul, 2012 21:41
Posts: 20

  Z3 roadster 2.2i

Service lights, myth or fact.

Post by broony »

I've had my Z3 about 2 months now and am very pleased with it( replaced a TR7V8).It had been serviced a couple of weeks before I bought it.I checked, new air filter, oil, plugs.However the service lights hadn't been reset.I'd read on this site that this could affect the ECU and therefore the performance so I bought the gizmo and reset the lights and at the same time fitted a freeflow air filter( Pipercross).
Now, the car definitely feels sharper.Is it really the case, or is it in my head? It's a 2.2l by the way.
Cheers Alan.
PS the plugs were a bit cheapo.Is it worth fitting "proper" plugs?
User avatar
BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
Posts: 2225

  Z3 roadster 1.9

Re: Service lights, myth or fact.

Post by BladeRunner919 »

I don't think anyone knows for sure, but it is a well held belief that as the service approaches the engine loses something.
Mike Fishwick
Joined: Fri 19 Jun, 2009 10:27
Posts: 2093

  Z3 roadster 2.8
Location: Daglan, France

Re: Service lights, myth or fact.

Post by Mike Fishwick »

It's true - I once ran mine untilthe red 'Service NOW' light came on, and then just reset the SI lights - the result was very noticeable. I find that this effect begins after losing about 3 1/2 lights, so now reset the lights (using a piece of wire) after losing the second light.

And no, I am not generally a conspiracy theorist, but it would be very easy to tie the ECU to the SI system, thereby gradually retarding the ignition timing to take the edge off the engine, and making people think that their £400 oil change was worth the money!
A Z3 is not just for Christmas - it's for life!
Radlitt
Joined: Thu 02 Sep, 2010 21:19
Posts: 55

  Z3 roadster 2.8
Contact:

Re: Service lights, myth or fact.

Post by Radlitt »

If true, a very clever yet dastardly scenario.

Jeremy
User avatar
Robert T
Site Admin
Joined: Mon 12 Jun, 2006 10:35
Posts: 10170

  Z3 roadster 1.9
Location: Cheshire

Re: Service lights, myth or fact.

Post by Robert T »

I'm a little less sceptical, but in theory, it could be that the performance is reduced slightly when getting near to a service to prevent damage to the engine. The only way to prove this would be to put the car on a rolling road immediately before and immediately after a service light reset and see the difference in power output. Any volunteers?

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
Image
User avatar
c_w
Joined: Thu 19 Aug, 2004 16:50
Posts: 4032

  M roadster S50

Re: Service lights, myth or fact.

Post by c_w »

I think it's placebo, on my car I have run it on full green or most lights out and don't notice difference other than the usual "good day" modes where it just feels a bit perkier. A battery reset seems to make a difference to me or changes in the way the car is driven, after a trackday it always feel quicker on the way home :D
broony
Joined: Mon 23 Jul, 2012 21:41
Posts: 20

  Z3 roadster 2.2i

Re: Service lights, myth or fact.

Post by broony »

Cars always feel quicker after being "excercised" fully. :)
User avatar
Brian H
Joined: Tue 16 Dec, 2008 19:55
Posts: 2505

  Z3 roadster 3.0i

Re: Service lights, myth or fact.

Post by Brian H »

I recently reset my service lights after an Oil Service and as sceptical as I was after reading other threads on the subject, there is a difference.
User avatar
PCSAM
Joined: Sat 13 Aug, 2011 01:19
Posts: 1002

  blank
Location: Taynuilt

Re: Service lights, myth or fact.

Post by PCSAM »

Brian H wrote:I recently reset my service lights after an Oil Service and as sceptical as I was after reading other threads on the subject, there is a difference.
but with nice new oil in it wont it run slightly better anyhow :?:
Image
User avatar
Brian H
Joined: Tue 16 Dec, 2008 19:55
Posts: 2505

  Z3 roadster 3.0i

Re: Service lights, myth or fact.

Post by Brian H »

PCSAM wrote:
Brian H wrote:I recently reset my service lights after an Oil Service and as sceptical as I was after reading other threads on the subject, there is a difference.
but with nice new oil in it wont it run slightly better anyhow :?:
I understand what you are saying, but I have never noticed a difference with any other car I have had after the service lights being reset.
User avatar
BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
Posts: 2225

  Z3 roadster 1.9

Re: Service lights, myth or fact.

Post by BladeRunner919 »

As Robert said, the only way we'll ever know for sure is with 'before and after' data from a dyno.
Vic-Z3
Joined: Fri 11 Jun, 2010 19:28
Posts: 915

  Z3 roadster 2.2i
Location: Redditch
Contact:

Re: Service lights, myth or fact.

Post by Vic-Z3 »

My 2002 2.2i is down to two green lights and feels a bit sluggish,
I am tempted to try the reset lights.
Might leave it until the two green lights are out, just before it gets the service.
----------------- BMW Z3 Das Beste Auto -----------------

Mein altes Auto riecht nach Nudeln, hat dieses Auto eine Wurst Geruch.
broony
Joined: Mon 23 Jul, 2012 21:41
Posts: 20

  Z3 roadster 2.2i

Re: Service lights, myth or fact.

Post by broony »

Let's face it, if there is a difference in power it's not going to be measurable on a dyno.If anything it's probably just a sharper throttle response.I hadn't checked for any faults before resetting the lights but afterwards none showed up on the code reader.I'm still puzzled by the low( 500/600 rpm) idle speed but as everything seems to run ok I've decided to let things be and stop checking.
Post Reply