engine not running properly

[mrdarcy]

i have an e30 320i tourer i have fitted a 2.5 engine in it , changed the ecu, the engine came from an auto and mine is manual, changed throttle body, maff air flow meter but it ran worse so put old one back on. have tried to alter the settings on the air flow meter with the alan key and the throttle body with the screw, it is running quite resonable . the bad bit in the mornings when engine is cold it runs very sick, running on not all cylinders, stalling and very difficult to drive , but when the engine starts getting warm it begins to run better. i am also only getting 15 mpg. the ecu unit came with the engine and is off an auto and as stated my car is manual , would anyone have any advice as this is driving me insane !!!!

[mrdarcy]

please help !!

[Grrrmachine]

If you've tampered with the AFM then you'll need to hook the car up to a gas analyser to set it correctly. As for the throttle body screw, it needs to be set to "click" the TPS as soon as the accelerator cable is pressed, otherwise the car will have no idle settings.

You don't mention what age the 2.5 engine is, and that is important; numbers from the ECU will help us determine which engine you have, and you should also check the part number for the AFM as they are different between 320 and 325.

Remember that when the engine is disconnected from the battery for a long time the ECU loses its settings. Idling it for 10 minutes, turning it off, then taking it for a red-line thrashing will allow the ECU to relearn the engine parameters properly.

If, after all that, the engine still fails to run correctly, we need more symptoms - long time cranking, lumpy hot or cold idle, stalling, lack of throttle response; all that sort of stuff.

And it's a TourING, not a tourer

[Grrrmachine]

And yet you're the one touting the Wiki

[mrdarcy]

hi thanks for responding. have been in touch with the person i purchased the engine from and he assures me it came from a 1989 facelift model. the ecu is a 55 pin, numbers to the left are 1726683 001 , and the numbers to the right are 0261 200 380. it is running lumpy hot or cold but worse when cold. it stalls sometimes at junctions, the throttle responce is instant but when you shut off out of the exhaust you get a blubbering. when engine is cold and when beginning to warm up you have to play with the throttle to stop the engine juddering . would be very grateful for you views . it is getting to a stage as to whether to scrap it and buy anither car as this is doing my head in big time !!!

[Grrrmachine]

ECU matches the engine, so that's ok.

Don't worry; you're not the first to suffer from these sorts of issues, and you won't be the last. You just have to be systematic with the solution.

Most likely you have an air leak; this means the engine doesn't know how much fuel to put in, so you get all sorts of power loss and rough idling issues. Have a read of THIS:

http://www.e30zone.net/e30zonewiki/inde ... #Air_Leaks

and work through it systematically. Even the smallest crack at the end of a hose can cause problems, so be thorough.

[mrdarcy]

i have sprayed brake cleaner on all pipes around the air intake system and no difference to engine idle. the idle control valve has been washed out and cleaned with brake cleaner. the pipe from the side of the inlet manifold [as thick as a pencil ] to the end of the fuel rail, when you take this off the engine picks up in speed, and when you put your finger over the end the engine goes back to running lumpy again. when you take the oil filler cap off the engine the engine picks up in speed but when you put it back on we go lumpy !! the engine was purchased from BIG BAVARIAN BEAUTIES near ipswich and i have asked for their help but they have no answers , they are supposed to be bmw specialists !!! i come from near march in cambridgeshire and am willing to travel a resonable distance to sort this problem. thanks for your help.

[Grrrmachine]

If you're absolutely sure there are no air leaks, (including the rubber plug under the throttle body), then start looking at rich running:

http://www.e30zone.net/e30zonewiki/inde ... ch_Running

[mrdarcy]

i have changed the blue sensor on the thermostat housing as i was told it could be that, the sensor from my old engine is on it as i know it works . wiring has all been checked. am totally confused and fed up this has beaten me . i have also had it on an emmisions meter and was set up by technician, but it still runs poorly and it even confused him !! a lighter would be helpful at this moment.

[jmc330i]

when you take the oil filler cap off the engine the engine picks up in speed but when you put it back on we go lumpy

Usually when the oil cap is removed with the engine running, it will run like a bag of poo, not the other way round.

[mrdarcy]

i no that this is confusing