Engine problems with 318i

[lukelio]

Hi. I have BMW 318i with M43 engine. I have engine check light on. It feels that car lost performance. Idle is jumping from 0.5 to 0.9rpms. I have changed o2 sensor, pcv, pcv hose(it was cracked), maf. Bmw scanner showed : "8D [141] Oxygen-sensor control, control limit" and "AB [171] Check, fuel supply system". Inpa showed : "141 lambda regulation control range block" and "171 Pruefung Kraftstoff-Versorgungssystem". I hope that you will help me to identify what part of my car is broken, because I will not pass car check-up.

[lukelio]

bump

[lukelio]

?

[shogun]

I assume it is an E36 EURO 318i, because in Europe the M43 TU was also used in early E46.
Be a bit more patient, you cannot expect an answer within such a short time from people from another continent, where the time is different.

[ultimatetester]

Clear the codes then figure out it's a vacuum leak somewhere

[ed323i]

Check the fuel pressure in the fuel rail (or let it be checked by a garage).. Perhaps your fuel pump is going bad and/or the fuel pressure regulator isn't working correctly.. Or the fuel filter is clogged.
If the injectors can't inject sufficient fuel due to too low fuel pressure, you'll get such an error.. Or, if the injectors are injecting too much fuel (outside of the ECU regulation range) due to too high fuel pressure (I once had a fuel pressure regulator stuck at 6 bar instead of the normal 3 bar), you'll also get this error..

You can also connect your car to BMW INPA software (if you know someone who has this).. Then it will show if the injectors are injecting too much or not enough gasoline.. But I would check the fuel pressure in the fuel rail.. Check the live adaptation values..

[lukelio]

Yes it is an european e46. I have two fuel systems so I think that the problem might be somewhere else?

[ed323i]

Is it an LPG (liquid gas) and gasoline car? Then it will probably do the cold start with gasoline and later on switch to LPG..
Do you notice any difference when it's running on gasoline or on LPG?
Are the problems only related to the idle or does it run badly overall?

If it's only the unstable idle, I would also check and clean the Idle Control Valve.

But the errors show that the ECU is unable to compensate enough w.r.t. fuel injection times.. The oxygen sensor keeps saying "this is way too rich" or "this is way too lean", and the ECU can only adapt a certain percentage (say 25%) from the values in the fuel map in its firmware. If the ECU has too correct beyond this, these fault codes will be thrown..

So, live INPA values, especially the adaptation values, would help a lot with the diagnosis.. And I would also have a garage/mechanic check the fuel pressure in the rail. Shouldn't cost too much if the garage has the right tools.

Also, if there is a problem with the gasoline fuel pressure, and the fuel is changed over to LPG (which probably has the right pressure), then the ECU will get very confused, and will show these specific errors I think.. (or vice versa: gasoline right pressure, but LPG pump not working properly for example).

What Ultimatetester wrote is good also: It could also be a big vacuum leak... Check all the rubber hoses near the engine and intake manifold and throttle body for cracks..

Good luck!

[lukelio]

Yes, it has LPG and gasoline systems and yes, when engine is cold it runs on gasoline and then it switches to LPG. I am not sure if there is any difference while driving in them, sometimes it seems that car looses power, but I noticed it only on LPG, because when the engine is not cold I am driving with LPG.

Sometimes the idle is jumping from 0.5 to 0.9k rpms. And sometimes car looses a lot of power ( especially now when the check engine light is on ).

I cleaned idle air control valve, changed maf, pcv, pcv hose behind engine.

I have scanned my car with inpa and scanner. This is the link to the scanning results : https://drive.google.com/drive/folders/0B5kf-piVE6V2U2NybHMxMERqemM?usp=sharing

I tried to look for vacuum leaks, but I was not able to find any new.

[ed323i]

I've given the values a quick look...
I think you might find the answer scanning this thread: http://www.bimmerforums.co.uk/forum/f18/2001-e46-318i-m43-engine-inpa-gives-error-code-171-a-t115824/
It's mostly related to vacuum leaks, and in the thread they show common sources of vacuum leaks for your engine..

Good luck!

[lukelio]

Thank you. I will read that thread.

[lukelio]

I read that thread. unfortunately I havent found anything new. I will try to make home-made smoke machine and test for vacuum leaks with it. I would appreciate any more advices