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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Discuss problems you have had or are having with your Z4
keith777
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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by keith777 » Mon Nov 06, 2017 11:29 pm

Mike, is water pump/ thermostat part of your repertoire?

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ph001
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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by ph001 » Tue Nov 07, 2017 8:39 am

There are no relays inside the pump but there are a ton of electronics in there which have probably gone faulty. As mentioned before, the stat has no sensors or electronics so is not really capable of causing the pump to run.
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by Newbers » Tue Nov 07, 2017 11:28 am

Pump (Pierburg) + stat (Wahler) ordered. I'll pick up some antifreeze from BMW on Thursday - anyone know how much I'm likely to need to replace by the time I'm done?
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by Newbers » Sun Nov 19, 2017 8:30 pm

I got a mobile ex-BMW guy out sort out my pump and stat. I gave £165 which included deleting a couple of codes. Quite an expensive episode....
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Ducklakeview
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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by Ducklakeview » Sun Nov 19, 2017 9:38 pm

keith777 wrote: Mon Nov 06, 2017 11:29 pm Mike, is water pump/ thermostat part of your repertoire?
Yes, I can do that for you. Only just seen post.

Mike

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by ph001 » Thu Jan 25, 2018 12:35 pm

Did changing the pump solve this OP?
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by Newbers » Sat Jan 27, 2018 3:30 am

Yes. That said, I'm not actually sure which was the culprit.
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by Wafoo » Sat Jan 27, 2018 10:20 am

Its a huge draw so look at things that can be attached to the battery that take a large current
My moneys on starter motor or Alternator
Merlot 2.2i SE, so far new discs and pads, seats replaced, Cam cover replaced, Roof now fixed, new diff x3, new halfshafts, new drop links and other bouncy bits,

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by Newbers » Sat Jan 27, 2018 1:20 pm

It was definitely the water pump that simply didn't turn off regardless of whether the car was running or not. I proved this with an ammeter and by pulling the fuse. The point is I'm not sure whether the fault was with the electronics in the pump or in the separate thermostat. Both have electrical connections but I didn't bother to investigate further, I figured replacement of both was quicker and cheaper + gave more future peace of mind than diagnostics.
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

Post by ph001 » Sun Jan 28, 2018 12:05 pm

:thumbsup:
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

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