E30 not starting / DME

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Fizzy123
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Post Sat Apr 24, 2021 11:03 am

Hello,

Just purchased a 1987 E30 320i

No start, fuel is being received to the engine and sparks at plugs, engine cranks.

Trying to locate the DME relay but can't seem to find it both locations mentioned (wing and bulkhead)

There is only a 7 pin fuel pump relay and that is all.

Can anyone help please :)

Thanks
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martauto
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Post Sat Apr 24, 2021 12:23 pm

Welcome to the zone mate, lets see some pics of the "offender" please ?
We all like pics!!
I`m sure some one will be along to help you out .

Mart.
Only the E46 cab left now.
Just got too old.
Fizzy123
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Post Sat Apr 24, 2021 1:57 pm

Thanks Mart,

Here goes

Here is the said fuel pump relay.. however I've just used the bridge method .. is there such thing as an all in one ?
20210424_133434.jpg
20210424_133538.jpg
20210424_133556.jpg
I bridge 30 to 87 and 87b and the fuel pump runs continously 87b .. when 87 is bridged a spark sound comes from the distributor.

We disconnected the following pipe and fuel came out
20210424_133604.jpg
Spark plug were checked each with a spark

I do want to check the CPS but no idea where it can be found.

There is a cable that goes to the bottom of the engine at the end of the injector line. The connector at the bottom is covered in oil, could that cause start issues ?

Here is an image of the engine bay
20210424_133419.jpg
Hope that helps

Fizz
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Brianmoooore
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Post Sat Apr 24, 2021 7:39 pm

It' a pity that the original owner of your car didn't wait a few more weeks before purchasing his E30! A massive upgrade in the engine electronics to Motronic 1.3 was made shortly after the production of your car - a system which is still similar to the electronics used today, give or take a sensor or two.
You have the earlier system, with its reliability problems, and the most likely thing preventing your car from starting is a duff crank position sensor.
Your car has two, mounted on the gearbox bell housing, next to the flywheel.
One of these sensors produces hundreds of pulses per revolution of the engine, which are divided down to produce the pulses for the sparks, and also integrated to provide the signal that switches on the fuel pump.
The other sensor detects a single magnet fitted to the flywheel, producing one pulse per revolution, which is used to determine the timing of the spark of one plug, and, by using the data provided from the first sensor, the timing of the other sparks. If your fuel pump runs, this second sensor is likely to be the problem.
The two sensors are identical, so you can compare resistance readings between them. Occasionally the sensor turns out to be fine, and it's the magnet in the flywheel that has detached itself.
Fizzy123
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Post Sat Apr 24, 2021 8:15 pm

Thanks for the headsup @brianmoooore

I'm assuming we have a motronic 1.0?

The internals are covered in oil so it's not been easy to trace routes . Are the CPSs are both easy to access ?

So managed to bridge 30 and both 87, and we get an odd cough.

Bought some engine spray and sprayed into the intake and it starts up and then dies again .

I'm guessing this means that it could be that fuel flow is not adequate ?
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Brianmoooore
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Post Sat Apr 24, 2021 8:35 pm

If it ran on gas, then both of the CPSs are OK. Needs both to be working for sparks.
Would be useful to get a cheap fuel pressure gauge on it, to see what's happening.
Fizzy123
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Post Sat May 01, 2021 12:06 pm

Hey,

Just for my knowledge and correct me if I'm wrong.

The CP sensors are located on the rear left hand side of the engine block .

Lifted the car up and this is what I've come across
20210501_120024.jpg
The image has been flipped 180

Is that normal ?the sensors are not there !
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Brianmoooore
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Post Sat May 01, 2021 12:24 pm

Curious! One thing for certain is that the car will not and never has run without a CPS.
Three possibilities.
1) There's an E30 CPS thief at large.
2) BMW used up stocks of the old type gearbox bellhousing on the first of the Moronic 1.3 cars.
3) Someone has done a conversion.

What ECU do you have?
Fizzy123
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Post Sat May 01, 2021 12:39 pm

Does this help
20210501_123745.jpg
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Brianmoooore
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Post Sat May 01, 2021 1:04 pm

309 is LE Jetronic!
Didn't realize that was still in use as late as '87.
Fizzy123
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Post Sat May 01, 2021 1:28 pm

So .. we have a LJetronic 😆

Next question ..

I guess we need to buy new sensors ? Where do they plug into
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Brianmoooore
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Post Sat May 01, 2021 1:48 pm

No sensors on these. This is really ancient technology - even calling the 309 an ECU is stretching things a bit by modern definitions.
You should have an old style distributor on the LH side of the engine block, with a rotating disc in it detecting the rotation of the crankshaft and producing timing pulses.
Any history of a cambelt change on this? The cambelt runs on what is described as an idler pulley in most instructions for changing M20 cambelts, with no reference to any timing of this pulley, since it only drives the oil pump. In your engine, however, it also drive the distributor, so it has to be timed correctly, or the spark timing will be out.
You need to check the ignition timing is correct. Start by turning the engine so that you know a cylinder is at TDC at he end of its compression stroke. This is when the valves are open on the complimentary cylinder (1 & 6), (2 & 5), (3 & 4). Remove the distributor cap, and confirm that the rotor arm is pointing at the pole that connects to the lead that goes to the plug of the cylinder in question.
This will not confirm accurate timing, but will check if it's in the ball park.
Fizzy123
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Post Sun May 02, 2021 2:07 pm

No idea when the Campbelt was last changed.

Whats the best way to move the cylinder 1 to TDC
. I know nooby question lol .. without manual crank
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Brianmoooore
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Post Sun May 02, 2021 2:18 pm

Has it run since a cambelt change, as far as you know?
Fizzy123
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Post Sun May 02, 2021 2:21 pm

Since we have had it (2 weeks).. it has never run fully.

AFAIK last time it could have run was when it had its last MOT back in 2013
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Brianmoooore
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Post Sun May 02, 2021 2:26 pm

Carry on and check the timing then.
Use a spanner on the crank pulley bolt to turn the engine forwards only
Fizzy123
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Post Mon Jul 12, 2021 2:27 pm

so a few minor updates, maybe due to the warm weather, the engine would start and would keep going when throttle is given.

There is constant white smoke when this is done.

when the accelerator is let go, it will either die or idle very badly (for less than a minute) until it dies.

We have removed the cylinder head and timing covers (Both crank and cam were at TDC)

we plan to replace the belts and gaskets just in case coolant is getting in the head. (THere is no milk gunk anywhere, just white smoke)

the valves on the camshaft are in the following position @ TDC, is that normal (See image)Image

Thanks
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riber3
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Post Sun Mar 06, 2022 8:53 pm

Hi there
Sorry to bother you did you resolve the problem ? and is it necessary to connect all 3 pins 887b, 87 and 30) (on the relay to test the fuel pumps? as my relay is pulling in but pump doesn't seem be running