2001 320i petrol 2.2ltr 6cylinder

If you are not a PicoScope user and want advice with a diagnostic problem then post here. Forum members may be able to help.
Post Reply
johnnypico
Newbie
Posts: 3
Joined: Fri Jan 18, 2019 10:31 am

2001 320i petrol 2.2ltr 6cylinder

Post by johnnypico »

2001 320i petrol 2.2ltr 6 cylinder e46
Has lpg fitted.
Car cranks over nicely just won't start. It try's to but won't. battery tested good. cam and crank signals there good. Replaced all 6 spark plugs new. Veryfied fuel injectionTested good. fuel pressure test good. The only code I pull of the car is 123 map cooling fault. But that's been faulty forever scanned car with ista . Shows 02 sensor signal banks 1 and 2 as short to ground / no signal . Have tested leads ohms resistance and all is good there on all 4 wires to each sensor. Even the heater to the 02 sensor has been tested good. Seems strange it's on all 4 sensors.When plugged in code reader the reading indicates that the key is being read and is working. have tested power to all 6 coils and thats good. also injectors are fireing. Compresstion test is good also. Does any one have any ideas which direction to go next. Should I be looking at ecu replacement? If so what's the best way to clone it?

ronw38
TwoWaves
TwoWaves
Posts: 65
Joined: Sun Aug 27, 2017 8:00 am

Re: 2001 320i petrol 2.2ltr 6cylinder

Post by ronw38 »

Hi JonnyP Is it dedicated LPG or dual fuel, was it running prior to the no start situation ? Check the basics if not already done, hook a timing light to #1 plug via an extension mark #1 TDC on crank pulley crank it to check basic timing, use easy start or some propellant to see if it fires thats it for now without more info. Cheers Ron One other thought its probably variable valve control if the intake valves are not opening as can happen with a failed system it will never start, remove the throttle body air hose put your palm over the intake crank the engine see if there is good vacuum.

johnnypico
Newbie
Posts: 3
Joined: Fri Jan 18, 2019 10:31 am

Re: 2001 320i petrol 2.2ltr 6cylinder

Post by johnnypico »

Hi thank you.
Car is dual fuel and has double vanos. The car will eventually run ! BUT have to crank it for ages. Fires a bit of the time getting longer each time till it eventually reaches full temp then runs . It will burn the starter out if continued to do so.
It's the starting from cold and keeping running .
Cam and crank look syncit but I Carnt find a known good to compare it with. Will do basic chq s as suggested thank you.
Back on it on Monday will try again. Only just got a picoscope so finding my way with it at present.

ronw38
TwoWaves
TwoWaves
Posts: 65
Joined: Sun Aug 27, 2017 8:00 am

Re: 2001 320i petrol 2.2ltr 6cylinder

Post by ronw38 »

Hi Johnny P I have spent a lot of time over the years with fuel conversion, from the early carburetor conversions, through to computer controlled gas injection. Isolate the LPG system and deal with petrol only. Turning of the tank valve is not a guarantee of fuel shut off as enough LPG may bleed past to enable engine idle, find the lock off valve in the supply line or it may be in the regulator both are solenoid controlled. If it is pre injection with a vapor hose to the intake system disconnect it and plug the openings. The reason is to avoid dual fueling causing hard start. With a dual fuel system you double your diagnostic woes so take LPG out of the equation, see how you go. Cheers Ron

johnnypico
Newbie
Posts: 3
Joined: Fri Jan 18, 2019 10:31 am

Re: 2001 320i petrol 2.2ltr 6cylinder

Post by johnnypico »

Just to update this as I forgot to.
Ended up replacing the ecu. Wireing to o2 sensors was bad so replaced wireing to them.
Just couldn't find anything specific to why would not start. Replaced ecu and it fixed it.
Serpriseing as ecu are normally reliable on theses.

Post Reply