Loss of power

UK forum for general and technical discussion about the Z3 roadster
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stupot50
Joined: Tue 07 Aug, 2012 08:35
Posts: 237

  Z3 roadster 2.8
Location: Torquay, Devon

Loss of power

Post by stupot50 »

My 2.8 seems under powered at low revs when cold, struggles to pick up speed in high gears. When the engine is hot it turns over 6 times when trying to restart it and then is very underpowered in all gears. Any ideas gents?
1999 2.8 Arctic Silver Z3
1987 Black Renault Alpine GTA V6 Turbo
2007 325d Msport - remapped
User avatar
colb
Joined: Sat 05 May, 2012 22:46
Posts: 690

  Z3 roadster 1.8 TU
Location: Newport South Wales UK

Re: Loss of power

Post by colb »

Put a code reader on it to see if it has set any codes that may guide you to what is wrong. Codes set may actually be caused by something else in the system so be aware that something in the system may be not working correctly and upsetting something else hence the codes you may see. A bad Maf is a possible cause it dosn't always set a code pointing itself out but causes codes such as exhaust sensors to be set as the ecu isn't getting the right info from the Maf. A Bad Maf may not set an engine management light and you could end up replacing sensors that are still ok. If you disconnect the Maf connection see how the car responds as it will revert to a default setting. If it runs and starts ok with Maf disconnected you will probably found the cause. Do not but cheap pattern Maf's go for either Bosh or Seimens OEM. The cheap ones are of doubtful quality and rarely last long if they work at all.
Whilst your under the bonnet check all rubber hoses for air leaks, any cracked hoses should be replaced, these engines are very particular with the induction side of the engine being airtight. Leaks will cause all sorts of running problems and codes being set.
Colb
1999 BMW 1.8 Z3
2003 BMW 2.5 Z4
1998 Honda Deauville NT650V
gookah
Z Register member
Joined: Thu 07 Aug, 2008 09:51
Posts: 2737

  Z3 roadster 2.8

Re: Loss of power

Post by gookah »

I have been suffering from a similar problem on my 2.8. Down on power and then recently started misfiring. No codes at all being set.

I disconnected the plug to the MAF and it restored everything. One second-hand MAF later and all is good again
this test costs nothing and takes 30 seconds. Try it first.
Image

Z3 2.8 Progress Journal (Mine)
Z3 1.9 Sport Progress Journal (Wifey's)

I have an element of 'M-styling' on my car, If that's a good enough reason for the manufacturers to adorn a 320 with the M badge, then its certainly a good enough reason for me..
Howard Adams
Joined: Mon 10 Oct, 2016 15:39
Posts: 57

  Z3 roadster 3.0i

Re: Loss of power

Post by Howard Adams »

Hi, sounds like a possible MAF, historically they don’t always generate a fault code. As mentioned in this post it’s always best to use a reputable brand..
Good luck.
NZ00Z3
Joined: Thu 23 Jun, 2016 01:26
Posts: 95

  Z3 roadster 3.0i

Re: Loss of power

Post by NZ00Z3 »

Sounds like an inlet cam sensor fault. You will need to read the fault codes in the DME to know for sure.
Howard Adams
Joined: Mon 10 Oct, 2016 15:39
Posts: 57

  Z3 roadster 3.0i

Re: Loss of power

Post by Howard Adams »

Hi, interestingly enough when my Z3 (3.0i) had intermittent loss of power it showed immediately on the code reader.
Camshaft sensors do seem to be a common problem with many Z3 (6cyl)
stupot50
Joined: Tue 07 Aug, 2012 08:35
Posts: 237

  Z3 roadster 2.8
Location: Torquay, Devon

Re: Loss of power

Post by stupot50 »

Had a scanner on it. Only code was cam sensor, replaced it and it's no different :cry:
1999 2.8 Arctic Silver Z3
1987 Black Renault Alpine GTA V6 Turbo
2007 325d Msport - remapped
mrscalex
Joined: Fri 13 Mar, 2015 09:14
Posts: 910

  Z3 roadster 1.9

Re: Loss of power

Post by mrscalex »

stupot50 wrote: Sat 21 Apr, 2018 07:49 Had a scanner on it. Only code was cam sensor, replaced it and it's no different :cry:
BMW part or 3rd party? Some 3rd party sensors are cr*p. Recommendation for critical stuff like this is BMW. Not cheap unfortunately.
ImageImage
2001 Z3 2.2 Topaz Blue (Trudy) - Keeper rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Cookies) - Keeper rebuilt having been bought with a seized engine
2002 Z3 3.0 Sapphire Black (Peanut) - Keeper awaiting rebuilding having been bought as an abandoned project
Plus Willy, Kodak & Maycee - All 2.2 Sport projects. Yes, 6 is a lot of Z3s :)
Always happy to try and help with spares :)
stupot50
Joined: Tue 07 Aug, 2012 08:35
Posts: 237

  Z3 roadster 2.8
Location: Torquay, Devon

Re: Loss of power

Post by stupot50 »

Not sure of manufacturer as it was supplied and fitted by an indie, trying to find out now
1999 2.8 Arctic Silver Z3
1987 Black Renault Alpine GTA V6 Turbo
2007 325d Msport - remapped
User avatar
colb
Joined: Sat 05 May, 2012 22:46
Posts: 690

  Z3 roadster 1.8 TU
Location: Newport South Wales UK

Re: Loss of power

Post by colb »

Have you disconnected the Maf electrical plug and tried the car as with it unplugged it should run on default settings. If it runs better then that would point to the Maf being bad. You could try cleaning it with Maf cleaning spray but cleaning rarely fixes a bad maf in my experience. As a replacement Maf is expensive is there anyone close to you with the same engine as yours who would be willing to try their working one in your car?
If you go down the replacement route make sure you buy a oem part Siemens or Bosch same for all sensors, cheap pattern parts are false economy, been there done that lessons learnt.
Colb
1999 BMW 1.8 Z3
2003 BMW 2.5 Z4
1998 Honda Deauville NT650V
mrscalex
Joined: Fri 13 Mar, 2015 09:14
Posts: 910

  Z3 roadster 1.9

Re: Loss of power

Post by mrscalex »

I'd rather have a secondhand OEM than new cheapo make.

I bought one recently for £20 and it's doing a good job.
ImageImage
2001 Z3 2.2 Topaz Blue (Trudy) - Keeper rebuilt from a write-off
2002 Z3 2.2 Titan Silver (Cookies) - Keeper rebuilt having been bought with a seized engine
2002 Z3 3.0 Sapphire Black (Peanut) - Keeper awaiting rebuilding having been bought as an abandoned project
Plus Willy, Kodak & Maycee - All 2.2 Sport projects. Yes, 6 is a lot of Z3s :)
Always happy to try and help with spares :)
stupot50
Joined: Tue 07 Aug, 2012 08:35
Posts: 237

  Z3 roadster 2.8
Location: Torquay, Devon

Re: Loss of power

Post by stupot50 »

Yes I have disconnected the maf, made no difference. Looks like my indie used a cheap sensor. I don't suppose anyone out there has a good one that they are willing to part with is there?
1999 2.8 Arctic Silver Z3
1987 Black Renault Alpine GTA V6 Turbo
2007 325d Msport - remapped
Robin82
Joined: Fri 28 May, 2010 02:04
Posts: 83

  Z3 roadster 1.9

Re: Loss of power

Post by Robin82 »

Had the same issue years ago, used a euro car parts Cam sensor and had no effect so ended up sending it back and buying OEM for £108. It improved but I still felt the power wasnt there. When my head gasket blew replaced the Crankshaft sensor and hey presto. Weird. A mechanic I spoke to said the two sensors can effect one another.
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