Z4 E85 3.0 - 2005 - will not start!

Discuss problems you have had or are having with your Z4
knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Thu Jul 22, 2021 1:52 pm

My son Ryan has a BMW Z4 E85 3.0 (2005). He loves the car, but we have not been able to get it started for a couple of weeks now! :(
I have checked the battery, alternator and starter motor, and all is OK. I have checked fuses & earth connections, and still no joy.
We have ordered a new ignition switch which should arrive tomorrow, I was wondering if the car key could be at fault... :|
Car is located in Burton on Trent. Any suggestions please?
Thanks - Kevin (Coventry)

User avatar
bigwinn
Senior Member
Senior Member
Posts: 1040
Joined: Wed Jul 08, 2020 7:13 pm
Location: Lincoln UK
Contact:

Z4 E85 3.0 - 2005 - will not start!

Post by bigwinn » Thu Jul 22, 2021 2:08 pm

Hi Kevin

Is it turning over or nothing at all

Lights on dash?

Cheers

Stuart
E30 325i Touring
E85 3.0i Sport
F31 330d

ON ORDER G21 330e touring M-Sport Plus Pack in Dravit Grey

User avatar
enuff_zed
Lifer
Lifer
Posts: 5053
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Z4 E85 3.0 - 2005 - will not start!

Post by enuff_zed » Thu Jul 22, 2021 2:12 pm

Hi Kevin,
Someone had a similar issue last week.
That turned out to be the battery. It showed 14.1v but (I'm no electrician) it wasn't pushing out enough amps to turn it over.
Diagnosed by jumping it from another car. Have you tried that?
E89 20i SDrive M Sport - Valencia Orange
E85 2.5i - Sterling Grey - Better half's fun car
E85 2.2i - Sapphire Black - Project Do-er-Up-er

knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Thu Jul 22, 2021 3:39 pm

Thanks for replies.
Car is not turning over, but lights on dash and radio working. I tried using jump leads using another fully changed battery but no result!

User avatar
enuff_zed
Lifer
Lifer
Posts: 5053
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Z4 E85 3.0 - 2005 - will not start!

Post by enuff_zed » Thu Jul 22, 2021 4:00 pm

knmstag wrote: Thu Jul 22, 2021 3:39 pm Thanks for replies.
Car is not turning over, but lights on dash and radio working. I tried using jump leads using another fully changed battery but no result!
Well there is history of the ignition switches failing, so fingers crossed its that simple.
E89 20i SDrive M Sport - Valencia Orange
E85 2.5i - Sterling Grey - Better half's fun car
E85 2.2i - Sapphire Black - Project Do-er-Up-er

User avatar
bigwinn
Senior Member
Senior Member
Posts: 1040
Joined: Wed Jul 08, 2020 7:13 pm
Location: Lincoln UK
Contact:

Z4 E85 3.0 - 2005 - will not start!

Post by bigwinn » Thu Jul 22, 2021 4:23 pm

enuff_zed wrote: Thu Jul 22, 2021 4:00 pm
knmstag wrote: Thu Jul 22, 2021 3:39 pm Thanks for replies.
Car is not turning over, but lights on dash and radio working. I tried using jump leads using another fully changed battery but no result!
Well there is history of the ignition switches failing, so fingers crossed its that simple.
That’s where I’d be leaning toward

No history of any aftermarket immobilisers fitted?
E30 325i Touring
E85 3.0i Sport
F31 330d

ON ORDER G21 330e touring M-Sport Plus Pack in Dravit Grey

Zedebee
Member
Member
Posts: 656
Joined: Tue Sep 29, 2020 10:37 pm
Location: North Hampshire

Z4 E85 3.0 - 2005 - will not start!

Post by Zedebee » Thu Jul 22, 2021 5:08 pm

Sorry you’re having difficulties. How do you know the starter motor is OK? This is quite a common failure and a do-able DIY fix.
Old boy’s toy E86 Monaco Blue 8)
Young man’s E85 2.5i Maldives Blue

knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Thu Jul 22, 2021 5:49 pm

Thanks for message. I removed the starter motor and tested it on the bench, using a spare car battery. Earthed the casting body, positive supply on terminal post, and bridged across ignition switch terminal. Gear pinion moved rearwards and was rotating at speed, all sounded fine. I therefore assume starter motor is OK.

knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Thu Jul 22, 2021 5:57 pm

Just in case anyone needs to remove the starter motor on a Z4, you do not need to remove the inlet manifold!
It’s possible to remove it on LHS, by removing air cleaner box and air mass sensor components. Thanks to YouTube video! :)

knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Thu Jul 22, 2021 10:53 pm

The new ignition switch arrived today, was fitted, but has not solved the problem. I plan to get a new key from a local auto. key specialist, but we are feeling very frustrated, having tried various potential causes, but still baffled!🙃

User avatar
enuff_zed
Lifer
Lifer
Posts: 5053
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Z4 E85 3.0 - 2005 - will not start!

Post by enuff_zed » Fri Jul 23, 2021 7:44 am

One last stab.
Is it an auto? Wondering if it could be a failure of an inhibit switch if so? Thinking it's not in Park?
E89 20i SDrive M Sport - Valencia Orange
E85 2.5i - Sterling Grey - Better half's fun car
E85 2.2i - Sapphire Black - Project Do-er-Up-er

knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Fri Jul 23, 2021 8:09 am

It’s a manual gearbox. I’m going to get a new key, as that can be a problem if it can no longer be read by the lock barrel. Thanks to all for suggestions.
Kevin

User avatar
enuff_zed
Lifer
Lifer
Posts: 5053
Joined: Wed Oct 26, 2016 11:05 am
Location: Attleborough, Norfolk

Z4 E85 3.0 - 2005 - will not start!

Post by enuff_zed » Fri Jul 23, 2021 8:38 am

knmstag wrote: Fri Jul 23, 2021 8:09 am It’s a manual gearbox. I’m going to get a new key, as that can be a problem if it can no longer be read by the lock barrel. Thanks to all for suggestions.
Kevin
Is it not possible to reprogramme the old key?
Don't you have a second key to try?
Unlikely for both to fail.
E89 20i SDrive M Sport - Valencia Orange
E85 2.5i - Sterling Grey - Better half's fun car
E85 2.2i - Sapphire Black - Project Do-er-Up-er

Mike6
Member
Member
Posts: 860
Joined: Thu Aug 20, 2015 1:17 pm

Z4 E85 3.0 - 2005 - will not start!

Post by Mike6 » Fri Jul 23, 2021 2:16 pm

I am the person with the fully charged battery with not enough amps to turn the starter motor. In this case I am still veering towards battery/starter motor. But the fact you tried a jump from another car does make me wonder a bit as mine then fired first turn of key. If engine is not turning it can only be a couple of things as circuit run directly from battery to starter via ignition. Not sure about failing battery in key, possibly a good try. I think these can be recharged enough by placing key next to a toothbrush charger.
You say you tested starter motor on a bench but it wasnt fitting against engine compression and additional forces. That still leads me to question the starter motor.

knmstag
Newbie
Newbie
Posts: 13
Joined: Thu Jul 22, 2021 1:37 pm

Z4 E85 3.0 - 2005 - will not start!

Post by knmstag » Fri Jul 23, 2021 6:15 pm

Thanks for support.
I will try a heavy duty battery from my Jaguar XJS, so worth a try. I will also check the voltage supply once again.
I plan to get one of the keys reprogrammed tomorrow.
It’s a process of elimination, albeit time consuming.
The Z4 is not the easiest car to work on! 😢

Post Reply