BMW M3

[xworks]

In the mean time I was at least able to use the laptop to set some things
up in "general engine setting" and check that the sensors were working
and feeding back some correct readings to the ecu.
Everything appears to be ok and there was no fires upon powering up
which is usually a good sign.

One of the area's I am a little confused on though (and there is many ) is the
crankshaft sensor signal.
I ran the Dta oscilloscope in DtaSwin to capture the signal and this is what I got......

The engine's fitted with a 36-1 tooted wheel and 2 wire Vr sensor and from
looking at the example screen shot's in the Dta manual my graph looks
a little flat?
Plus, the text under the graph says the crank position is either 27 or 207
degree's and I'm fairly sure I set the leading edge of the next tooth after
the missing one around 90degree's after TDC when installing the toothed wheel.

If anyone can shed any light on any of the above I'd appreciate it.

[stevieturbo]

The trailing edge of the tooth after the missing tooth needs to occur before cyl1 TDC. Not after it.

Visually check this and enter the degrees this happens before TDC. Dont guess.

then when it is running check and fine tune with a timing light

[xworks]

Fairly sure I messed that up then, I have the exact degree figure written down
in the engine build log somewhere after fitting the wheel. It was either 90 or
91 degrees atdc. Will the ecu still work with with a placement of 270 degree's
btdc or would it be better to remove the pully and refit the wheel?
Thanks for the reply by the way.

[grant620]

Awesome project. Got a soft spot for the E30.
We have some 1.05 bar map sensors on the shelf that I can do real cheap.
99.9% of our customers are turbo customers so these have been here for a while.
Brand new - £35 delivered.

[Roverdose]

my graph looks a little flat?

does it have plugs in?

Drew

[stevieturbo]

Fairly sure I messed that up then, I have the exact degree figure written down
in the engine build log somewhere after fitting the wheel. It was either 90 or
91 degrees atdc. Will the ecu still work with with a placement of 270 degree's
btdc or would it be better to remove the pully and refit the wheel?
Thanks for the reply by the way.

basically as you are rotating the engine clockwise. The sensor needs to see the gap before TDC so it can tell the ecu TDC is coming up. It's no use telling it...oh TDC happened a few minutes ago.

Although I think the S-series is more flexible than the old ecu's So you may get away with telling the ecu that No1 TDC is going to happen in 270deg, rather than the 90deg you thought.

Just make sure firing order etc is all correct for where you're setting no1 Cyl at firing TDC in relation to this missing tooth setting.
Other than that, I dont see why it would pose a problem

[xworks]

We have some 1.05 bar map sensors on the shelf that I can do real cheap.

Thank you for the kind words and the offer, had we crossed paths a month ago
I almost certainly would have purchased your map sensor, however as things stand
I bit the bullet and purchased a Bosch one from the local motor factors.
(for a damn sight more than £35 too )

does it have plugs in?
Drew

Hello Drew,
No, plugs weren't fitted for the cranking during the oscilloscope test.
Is this how the test guestimates the TDC and cps location by the crank speed
approaching and after compression?

It's no use telling it...oh TDC happened a few minutes ago.

Cheers, hands up it was was just a pure brain fart on my behalf fitting the
trigger wheel. Had the pulley faced down on the bench when positioning and
welding on the trigger wheel and never twigged it till I read your post last
night.
Shall redo the measuring for the current location on the missing tooth and enter
it into the settings.

On the other point, has anybody any ideas how I might go about obtaining a
base map to start this engine before I bring it to the tuners?

Thanks again,
Brian.

[welshpug]

dta might have something suitable or know someone who's done something similar?

[stevieturbo]

Base Map....do it yourself.

If you're already working through all your sensors and getting sensible readings, then that is the hardest bit sorted.

Fuel wise, start with the main map numbers low, and add fuel there to get it to start. Have the engine warm up and then adjust the fuel map up/down until it is idling with a sensible mixture. That's half the battle over.

Dont even go near cold start or any of that stuff until you have the engine at least starting and idling properly when warm.

[Roverdose]

Hello Drew,
No, plugs weren't fitted for the cranking during the oscilloscope test.
Brian.

thats why it looks flat.

Drew