Help needed for a very disheartened zoner :(

[zimmerkid]

Could somebody outline the possibility's of why my m42 wont run under load?

engine is out of a '94 e36 318is, has ecu off the same car, using an e30 318is engine loom.


The engine will run fine on tickover, when it is revved and held for a minute or so the engine basicaly cuts out until the throttle is let off,
I took it out the other day and whilst cold drove fine to the garage, then on the way back when it had warmed up a bit it was that bad it wouldnt move.
when you build the car up into high revs it will keep revving and move which in my (not very e30 educated) mind rules out starvation of fuel/air and a spark problem!

Have tried a seperate set of coil packs just to rule that out, and have also searched for vacum leaks using the gas from a blow lamp and by taping/bodging the vacum hoses up with insulation tape all to no avail!

If anyone can help me with this it would be very much appreciated as i need my car back by monday!!
Thanks in advance!

[caneswell]

Coolant temp sensor?

[alync205]

You could try/check the crankshaft sensor.It should have a reading of approx 550-600 ohms resistance I think.

[zimmerkid]

Coolant temp sensor?

Havent checked this. can this be checked with the multimeter? what should it read?

AFM may be causing this, see if you can find a known working one to try out.

Have my old one on from the m40 engine was working fine on the m40! I read somewhere that they are the same part number? can anyone confirm this?

You could try/check the crankshaft sensor.It should have a reading of approx 550-600 ohms resistance I think.

Checked this and was getting around 500 ohms which i thought wasnt to far off!

Thanks for all the replies guys im all outa ideas will get a coolant temp sensor and see if this works
does any body know if my old temp sender to the dash board from the m40 engine will work the same in the m42? Im sure the part # are the same on real oem??
Thanks again

[Falkster]

I had this on my Evo and I thought it was AFM as everything pointed toward it. Turned out to be my fuel pump.

[mr_dink]

I found the AFM was a bit bigger on the m42 when I swapped from m40.

[alync205]

On RealOem it seems to show the same part no. for the AFM on a 318i anyway,316i must be different.
You can measure the coolant temp sensor with a multimeter but you need to knoe the temp as the resistance change with the temperature.It is the blue sensor you would want to try as the brown one is just for the gauge, the blue one is for the ECU.

[zimmerkid]

Tried a new coolant temp sensor today and still made no difference, oil light has also come on faintly!
could a small amount of oil leaking from the sump create these problems? the oil is coming from the gasket not a crack in the sump!
Thanks for the ideas! is there anymore possibilitys??

[zimmerkid]

can anybody help me with this as my car still wont run properly after a simple engine swap and is really annoying me now!
Please any more ideas would be greatly appreciated

[Nay]

Are you positive its the E36 M42, and not the later E36 M44 engine which is the 1.9L (iirc). I mean, doubtfull, but could well be. Then I'd be looking to make sure the looms are actually compatible. It running at all though probably rules that long shot out.

As above, have you checked the fueling? Fuel Pressure regulator hasn't gone?

But to me does sound like a sensor/ECU problem. Would an engine diagnostic tool help figure out this problem?

Dont take anything I say seriously though, never had this problem!

Good luck. I'm stuggling to finish my rebuild too... I know what its like

[Brianmoooore]

Check the the throttle position sensor turns the same way on your new engine as on the iS. If it goes the opposite direction and you are using an E30 loom, it may be telling the ECU the throttle is closing when it's actually opening.
I vaguely remember that this scenario can happen somewhere in the world of BMW engine swaps.