Engine Died when put in Drive (Solved)

Post here for mechanical and engine topics such as fuel issues, transmission problems, rough idle, exhaust, electrical issues, etc

Moderators: GRNSHRK, ron, bfons

User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Engine Died when put in Drive (Solved)

Post by TomMan7531 »

Hi,

So went to start my 635 today and started fine, put it into drive and died. Went to restart and it cranks but won't fire, please help.

Thanks.
Last edited by TomMan7531 on Wed May 16, 2018 11:31 am, edited 1 time in total.
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

could be any one of the usual causes of a no-start.

That it happened in the way it did is suggestive of a fuel supply problem, but there is no proof of that until you test.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

Well I tried spraying starter fluid into the air intake and nothing going, still just cranking
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

you need to check spark, injector function, fuel pressure, cold start injector function.

Given that it doesn't fire on eezy-start, I'd say you have no spark, but it is easy enough to verify that.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

Update now is there is no spark in the spark plugs but distributor and leads do look in good condition. Looking on the angle that it died when put in drive I've taken out the gearbox ECU and then my eyes watered at how much they go for.. \:D/

I'm trying to find a K gearbox ecu to test near where I live to check if that's causing trouble but would a broken ECU stop spark in the plugs??

Besides that I'm stumped, not great with engines. ](*,)
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

the gearbox ECU has nothing to do with the running of the engine. The only thing that the gearshifting arrangement does to the engine is that it inhibits the starter when the gearstick is in certain positions.

You are likely to generate further (unknowable, unfixable) problems if you carry on down this route.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Pod
Platinum Member
Platinum Member
Posts: 4492
Joined: Tue Mar 16, 2010 8:32 pm
Location: usually in the barn, Kent, England.

Re: Engine Died when put in Drive

Post by Pod »

You need to go back to basics and find out why you have no spark. There is a great deal of advice on this forum if you search!

Have you checked the two sensor leads which go to the gearbox? Sometimes the connectors to the loom need to be disconnected and cleaned.
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

Yeah the ECU was a suggestion on Facebook but yeah have put it back in in fear of breaking it.

These two sensors, are they on the bottom of the engine?
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

my point was that there is no point in playing with the gearbox ECU because it cannot stop the engine from running.

Test #1 is that you have a good 12V feed to the coil (one that will not droop when you are using >20W test bulb on it).
-test #2 is the injectors similarly have a good +12V feed
- test #3 is to measure the impedance of the crank sensors (LH side of bellhousing, harness connections on rear manifold brace and at engine ECU plug)

A full set of tests is detailed in any half-decent workshop manual. If you have not got one, get one.

ECU pin outs are in the ETM.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
86_6series
Platinum Member
Platinum Member
Posts: 1069
Joined: Mon Apr 02, 2007 10:08 pm
Location: West Nyack, NY

Re: Engine Died when put in Drive

Post by 86_6series »

Best get the ETM for your car http://wedophones.com/Manuals/BMW/

and use this to help troubleshoot your no start. http://www.hiperformancestore.com/motronic.htm

Don't do guess work. You must methodically

go thru the systems, checking for possible problems. We're here to help in any way.

Because the car died when shifting into drive, I can see where you think there's a connection.

Until you find the problem, I think it was coincidental.

On this site there are hundreds of years total experience with these e24's.

We'll be cheering you on to solve your no start.

Bob V
86-635CSi
96-MB C220 SOLD
98-740i
71-Continental MK3
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

http://www.hiperformancestore.com/motronic.htm has been suggested a few times but website is dead ](*,)

So far I've checked and I do have a 12v feed to the coil on crank, and when putting the positive lead of a multimeter into the center of the coil and the black to ground I get 5.5k Ohm with ignition on.

The crank position and speed sensors have been confusing me, I have attached a picture with the two circled? Gone to the other end with the two in the bell housing on the gearbox and they dont look in bad shape, gave them a clean and tried to use the multimeter on the circled ones again and using the AC standard as the guides suggested got no reading with ignition or crank however as there are three pins its likely I'm just using it wrong. I have also listed a picture of a connection on the thormstat housing?? and looks in bad shape as hopefully the picture shows, would this cause an issue?

Besides that I will read through that guide and thanks for provding but hate engines and hate electrical systems so this is my idea of hell.

Thanks.
635csibay2.jpg
635csibay2.jpg (182.54 KiB) Viewed 11722 times
20180325_183522.gif
20180325_183522.gif (539.47 KiB) Viewed 11722 times
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

the two connections at the rear of the engine bay are for the crank sensors on the bellhousing as described previously. These need to be good connections and the sensors need to measure as per the manual (~1000 ohms between the end pins IIRC). DO NOT swap these connections over; if you do the engine cannot run. To ensure that this does not happen it is best to unplug them one at a time.

The connection at the front of the engine goes to a third crank sensor. This is not used in the normal running of the engine; it is only connected to anything when you have a BMW service tool plugged into the diagnostic port.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

I might have assess to another crank position sensor to diagnose, I'm guessing the two of them are the same senors just reading different things?
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

they are the same part, yes reading different things (speed and ref). No need to guess BTW, they are indicated as the same part number in the ETK

(IIRC the unused front crank sensor also reads ~1000 ohms too.)

BTW there is a grey plug and a black plug and one goes to speed and the other ref. One of the sensors usually has a zip tie around it and that also helps identify it. I can never remember which is which with absolute certainty; I always have to check.... :roll:

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

One does have a zip tie yes, I'm guessing getting them out from top to bottom will be a pig \:D/
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

So latest is still nothing

Got a brand new crank sensor and tried interchanging the two with an old one but nothing

Now replaced the distributor cap and rotor arm as both were in a bad way but still nothing... Just getting crank with no spark.

Please help! ](*,)
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

there is no point in just randomly replacing parts; the idea is that you test them and replace them if faulty, not that you very slowly and expensively buy a new car, one random part at a time....

BTW there is also no point in doing half-arsed tests; for example I specifically recommended that you tested the coil feed for +12V using a load (eg test bulb of at least 20W rating, seeing that the voltage does not change under load), because that feed needs not to droop under load, which is a common fault on these systems. You measured it with a multimeter and it shows 12V but that is 'necessary but not sufficient' to prove that it is any good. Having carried out that half-assed test, you could spend days effing about with the rest of the system and it could still be that the 12V feed is not good enough.

The wayback machine has a version of the Hiperformance Motronic guide. The guide isn't perfect BTW but it better than nothing. [Also good for this purpose (better in fact) is/was Rick's no-start 6er page (link in tech articles). I think the link is now dead but someone (Chris Wright?) has an archived version somewhere I think.]

https://web.archive.org/web/20110810113 ... tronic.htm

BTW there is a wire that is attached to the starter motor that sends a 'start signal' to the ECU (pin 4) during cranking and it also appears at the diagnostic socket. If this connection is bad then you get a crank but no spark symptom, but it wouldn't stop the engine from running once it was running. Thus if you have that fault then it is probably not the only one.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

Thanks Brucey,

I did only replace the distributor cap because it did look corroded which the guide did recommend. Having said that reading the guide on the wayback machine (thanks for this) has a section for checking the fuel injector, mine with ignition on was reading nothing where it should be a 12v feed.

Then following the guide back to the main relay it says check terminal 30 and 86 for a 12v feed with ignition and mine is getting some voltage but not a consistent 12v and is bouncing all over the place bewteen 0-12v???

The guide then mentions about it going through the 13button OBC in the cabin? Mine does seem to working fine but could someone confirm if this could cause an issue, besides that its the ignition switch, wiring or ECU according to the guide that has an issue but the guide mentions nothing about voltage bouncing all over the place on the main relay socket
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

dunno why you should get a fluctuating voltage at the main relay socket, unless there is another problem (eg in the fuse box? or ignition switch).

Suggestion; put a load on the 12V feed (eg a test bulb, below the fused rating of the circuit obviously) and see how the voltage looks then.

BTW problems inside the fuse box are not unknown. Nor are problems in the OBC immobiliser circuit.

You may seen my post explaining how to put jumpers in the main relay socket; if the relay itself is bad or the feed (via the ignition switch etc) for the coil is bad then you can temporarily bypass these parts of the circuit. Not safe to drive the car like this, since the fuel pump will run all the time, BTW.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

Ill look more this evening but if I did do the relay wire guide you've done would 13amp wire do the trick? And if so I'm guessing what see if the car starts then if it does turn it off quickly?
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

best if you make up leads with crimp terminals on them, otherwise there is a danger of stray strands bridging contacts that you don't want.

Car will run quite happily with the jumpers in place. The reason it isn't safe to drive the car is that the fuel pump won't shut off in the event of a prang.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

Ok so wiring past the main relay didn't work.
I wasn't getting weird voltages just wasn't getting a good ground, all injectors are fine as is the main relay socket, water temp sensor fine, ignition coil fine, crank sensors are fine distributor cap and rotor are brand new, everything checks out and at this point I'm really starting to loose patience, anyone got any more ideas?
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

you don't mention having chased down the 'start signal' I mentioned above

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
User avatar
TomMan7531
Posts: 68
Joined: Fri Feb 24, 2017 1:20 pm
Location: Southampton, Hampshire, UK

Re: Engine Died when put in Drive

Post by TomMan7531 »

If you mean check pin 4 at the diagnostic port it was reading a steady 4. 4 volts, dropped when cranking to 3-4 but battery was weak.
1987 BMW 635CSI Auto, Royal Blue, Cream interior, daily rust finds....
User avatar
Brucey
6 Series Guru
6 Series Guru
Posts: 10077
Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: Engine Died when put in Drive

Post by Brucey »

it is (IIRC) pin 4 on the ECU, which I think I said. Since the voltage at the diagnostic port (different pin number there, see wiring diagram) is not proof positive that the signal is good at the ECU where you need it, I recommend that you verify it at the ECU if you want to be certain.

However it is easy to check at the diagnostic port; if the signal is not present at the diagnostic port and you have a no-spark condition the most likely thing is that it isn't present at the ECU either, and that is the reason why your engine won't go.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Post Reply