E36 cutting out and draining battery

quattro Rick

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quattro / M796
Right so I've a couple of issues that have been popping up intermittently, first of the engine cuts out when coming up to a junction, there's no real indication unless you're watching the rpm needle and see it fall below 700...

Initially I thought this was the vacuum boot from the airbox to the ASC throttle body, but having deleted the ASC completely and used a brand new Z4 boot and hose, it's still happening. I've still not got around to replacing the vanos seal and anti rattle bearing, this is what I'm thinking it might be, but I'm also wondering should I be looking into possibly more vacuum leaks hidden elsewhere?

Then there's the battery which if the car hadn't been used for say 4-5 days would need a jump, I've replaced the battery as it was knackered and didn't hold a charge, was left on a charger for a day or two and when re fitted still needed a jump, no issue since the new battery with regards to starting

However when I hooked it up the hazards were going mental with the car locked and unlocked with the hazard switch off, it would stop for a minute then as soon as I started driving again would kick in again

I fished about under the gear gaiter and found what I think might be the fault, a previous owner installed one of those illuminated gear shifts, which I think was hooked into the hazard cable for power to illuminate, when I pressed the hazard button the doors would lock, which I found strange as there is no button to lock the doors inside, I disconnected a cable which stopped the flashing, and all seems ok now, but I'm curious if this may have been what triggered the battery drain?

Or else I believe it may be from the heater unit, as when the car is turned off I can still hear the fan under the unit whirring away, I've since disconnected both the head unit and the heater unit to see if he car will sit for a few days and start ok.

The hedgehog has been replaced so I doubt it's that, but who knows maybe I got a dud

Thanks for any insight, I'm sure there's a wealth of knowledge on these as everyone and their granny seem to have owned one at some stage 🤣
Said heater unit fan
20191013_202701.jpg
 

Phil_EK9

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Dungannon
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FN2 CTR/E36
The car cutting out sounds the same as when my cam sensor failed. Best to scan it, you'll need an adapter to connect an obd2 scanner to the socket in the engine bay. Like this:

Amazon product ASIN B00SV3GNE0
Not sure about the heater, think its done it to me a couple of times 😂. Wish I had the manual heater, far better job
 

mayweather

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M3 Evolution
I’d change the cam Position sensor and failing that, the crank position sensor.

Hopefully this isn’t a ball ache
 

quattro Rick

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quattro Rick
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The car cutting out sounds the same as when my cam sensor failed. Best to scan it, you'll need an adapter to connect an obd2 scanner to the socket in the engine bay. Like this:

Amazon product ASIN B00SV3GNE0
Not sure about the heater, think its done it to me a couple of times 😂. Wish I had the manual heater, far better job

Will have to get myself an OBD2 scanner 🤣

Sure if I'm doing the vanos repair the cam sensor shouldn't be too difficult to do then if that's the problem! 👍

Will definitely get it scanned first though to be sure, sensor looks to be about £80ish from ecp

I rarely use the heater anyway ffs, it turns itself on any time I turn the car on, then I turn it off, and it still whirrs away when turned off. Going to split it and see if there's a dust build up in the fan

Cheers for the advice!
I’d change the cam Position sensor and failing that, the crank position sensor.

Hopefully this isn’t a ball ache

Hopefully one of those two, is the culprit, will get it scanned and see what I can see

Reading about the cam sensor, supposedly when they go the cars down on power/torque, so might have a bit more pull if that's the case

Cheers!
 

Phil_EK9

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Dungannon
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FN2 CTR/E36
Will have to get myself an OBD2 scanner 🤣

Sure if I'm doing the vanos repair the cam sensor shouldn't be too difficult to do then if that's the problem! 👍

Will definitely get it scanned first though to be sure, sensor looks to be about £80ish from ecp

I rarely use the heater anyway ffs, it turns itself on any time I turn the car on, then I turn it off, and it still whirrs away when turned off. Going to split it and see if there's a dust build up in the fan

Cheers for the advice!


Hopefully one of those two, is the culprit, will get it scanned and see what I can see

Reading about the cam sensor, supposedly when they go the cars down on power/torque, so might have a bit more pull if that's the case

Cheers!

This is a good job, will do ABS, airbags etc. Along with engine codes.

Amazon product ASIN B00KL4H2G0
This is a good cheaper option if you just want engine codes

Amazon product ASIN B07QV1X93J
 

quattro Rick

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quattro Rick
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DMC 4087

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1,501
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Newry
Sounds similar to what was happening with our e36 recently which had a massive battery drain. All sorts of crazy things were happening with the electrics/engine running. Traced the 'leak' to the alternator.
 

quattro Rick

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quattro Rick
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Sounds similar to what was happening with our e36 recently which had a massive battery drain. All sorts of crazy things were happening with the electrics/engine running. Traced the 'leak' to the alternator.

Will get it tested too 👍 thanks

Think I had noticed some audible hissing through the speakers a while back, but that was on the old battery, must double check
 

quattro Rick

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quattro Rick
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Unsure as to what my present alternator is for Amp A ratings, but the two offered seem to be 90 amp a or 140 amp a, if the alternator needs replaced should I just go with the 140 version?
 

DMC 4087

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I just fired the part number into ebay and picked up a second hand unit.

My battery was draining something massive like 4 amps. Disconnected various things before getting to the alternator - the amps dropped immediately after unplugging it.
 

surprising_skoda

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Skoda/BMW/Austin
Will definitely get it scanned first though to be sure, sensor looks to be about £80ish from ecp

Go genuine or don't bother.

I've fixed so many cars by just replacing spurious cam and crank sensors with genuine ones. Complete waste of time and I would check that they are genuine as giving intermittent signals that mean you can start the car but it cuts out is a common symptom of them. Also unplug your AFM and see if it still cuts out then, if you've not tried that yet.

As for the heater, could still be the hedgehog, try again, and the heater panel is also a potential culprit for the battery drain / blower staying on.
Obviously the right way to test this is to switch the car off, leave it 20 minutes then take a multimeter to your fusebox and see which circuit has a draw on it.
 

quattro Rick

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quattro Rick
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Go genuine or don't bother.

I've fixed so many cars by just replacing spurious cam and crank sensors with genuine ones. Complete waste of time and I would check that they are genuine as giving intermittent signals that mean you can start the car but it cuts out is a common symptom of them. Also unplug your AFM and see if it still cuts out then, if you've not tried that yet.

As for the heater, could still be the hedgehog, try again, and the heater panel is also a potential culprit for the battery drain / blower staying on.
Obviously the right way to test this is to switch the car off, leave it 20 minutes then take a multimeter to your fusebox and see which circuit has a draw on it.

The one on ecp I was looking at is a Delphi, would that not be adequate? Happy enough going genuine if that's the best course though.

Will disconnect the AFM too and see what that does, and will get a multi meter on it asap cheers!
 

Gemma

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10,056
Could be the hedgehog. Mine did this in the five series.
Wouldn't turn on one day. New battery, next day dead as a dodo.
It was the hedgehog.
Fan whirring away when I had the car turned off but never thought anything of it
As for the cutting out, could be an air leak. Get a smoke test done?
 

Phil_EK9

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Dungannon
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FN2 CTR/E36
The one on ecp I was looking at is a Delphi, would that not be adequate? Happy enough going genuine if that's the best course though.

Will disconnect the AFM too and see what that does, and will get a multi meter on it asap cheers!

There is a lot of forum talk about using genuine sensors. Think mine was £120 a few years back, though that was for a 4 cylinder.
 

quattro Rick

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quattro Rick
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There is a lot of forum talk about using genuine sensors. Think mine was £120 a few years back, though that was for a 4 cylinder.

Think we've an account with Bavarian so might get it scanned then priced up if it's faulty

Do you still have yours? Just seeing it was a Fern green one 😲
20190412_155236.jpg
 

chrisdromore

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Voltage regulator caused all sorts of madness of my bm. Some like what you report.

Can you check the voltage some how whilst your out and about? Is there a hidden menu on e36
 

quattro Rick

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quattro Rick
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Aye, sitting rotting in the driveway as I can't find the energy to work at it 😂

I think I'll enjoy mine a touch more if I ever get round to getting an exhaust... Getting into it after the rs6 is a world of difference

Might have one fabricated just from the last section back, thinking two parallel straight pipes with a butterfly valve would keep it quiet but loud on WOT 😏
 

quattro Rick

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quattro Rick
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So I think I've pinpointed a few issues which might be the cause of the above faults, battery seems a ok, left the car a week without being moved and no trouble cranking over so that I imagine was to do with the battery, will get the alternator tested once I get my hands on a volt meter

As for the cutting out, I noticed while doing the code reading that I could hear a hissing, looked over to the fuse box to be greeted with a tasty bit of wire/hose munching

20191026_194030.jpg


Fault reader threw up vanos and cam sensor faults so they'll be getting sorted asap, still haven't got round to doing the vanos but I'll make a point to do it soon

20191026_193528.jpg
20191026_193535.jpg
20191026_193700.jpg


Looks like I may also have an injector issue? 🤔
 

Phil_EK9

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Dungannon
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FN2 CTR/E36
So I think I've pinpointed a few issues which might be the cause of the above faults, battery seems a ok, left the car a week without being moved and no trouble cranking over so that I imagine was to do with the battery, will get the alternator tested once I get my hands on a volt meter

As for the cutting out, I noticed while doing the code reading that I could hear a hissing, looked over to the fuse box to be greeted with a tasty bit of wire/hose munching

View attachment 254908

Fault reader threw up vanos and cam sensor faults so they'll be getting sorted asap, still haven't got round to doing the vanos but I'll make a point to do it soon

View attachment 254905View attachment 254906View attachment 254907

Looks like I may also have an injector issue? 🤔

Did you clear the faults before running the car and checking again? Sometimes codes hang around if they aren't cleared.
 

quattro Rick

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quattro Rick
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Did you clear the faults before running the car and checking again? Sometimes codes hang around if they aren't cleared.

Didn't think of that, will give it a clear and try again, though I'm sure both vanos and cam sensor are needed as it's rattly and idle bounces about. Cheers
 
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