Running Problems (Non Volvo)

[Dave86]

I'm now a traitor and have defected to the germans and im having some issues with it as follows;

1. Car lacks power in general (Not helped by only having a 1.9 8v engine)
2. At first start up it idles perfectly but when you start driving it pops and bangs hesitates then after a minite its ok
3. At WOT it loses nearly all power until you back of slightly then pulls ok

Found all the air leaks and have repaired them, only 1 code comes up which is P0170 (Fuel trim malfunction - Too lean)

Long Term Fuel Trim is about +22%
Short Term Fuel Trim is the same

O2 sensor 1 voltage at idle fluctuates between 0.4 - 0.6 which i think is fine
O2 sensor 1 voltage while driving is 0 - 0.1 (This is not just under heavy load it also reads this while maintaining a constant speed on flat road)
When coasting the sensor sometimes flashes 0.8 - 0.9 for a split second them goes straight back to 0.1

O2 sensor 2 seems to read fine at all times and generally stays between 0.4 - 0.6 under most driving conditions

No black smoke from the exhaust the exhaust gases don't smell overly petrol-ly (I'm sure that's not a real word)
So i'm assuming its not over fuelling

Recently changed the cam sensor as that was throwing a code also changed the fuel filter, Both within the last couple of weeks

I've tried checking the fuel pressure by pushing the schrader valve on the fuel rail but I couldn't get anything to some out even with the engine running which seemed strange
Although I would of thought low fuel pressure would of thrown a code?
Or if there was no pressure it just wouldn't run at all.

These a whole list of things it could be according to google, I'm just trying to narrow it down a bit.

Any advice appreciated
If it helps the car is a 2001 BMW 318 with a M43TUB19 engine

Cheers
Dave

[Kingsford G]

Have you tried unplugging the maf?From what you saying O2 sensor 1 if messing around big time,when it goes 0.9 is the tolerance of rich fuel and then drops down to 0.1 is very lean.I had a 318 maf messing around no engine light on.Try disconnecting the maf,it`ll be juicy but should run fine if so get a new maf.Nice looking car mate.Ah,also mine was lacking power too.

[nobananas]

Could be a dieing fuel pump, you won't get a low fuel pressure code from a petrol.

[Dave86]

Have you tried unplugging the maf?From what you saying O2 sensor 1 if messing around big time,when it goes 0.9 is the tolerance of rich fuel and then drops down to 0.1 is very lean.I had a 318 maf messing around no engine light on.Try disconnecting the maf,it`ll be juicy but should run fine if so get a new maf.Nice looking car mate.Ah,also mine was lacking power too.

Cheers ill give that a go tomorrow mate

Could be a dieing fuel pump, you won't get a low fuel pressure code from a petrol.

I thought about the pump too. Is there a way to check it?

[Kingsford G]

You need a gauge to check the fuel pressure mate.Try the easiest maf if no joy I recon low fuel pressure form pump,maf could make it run lean too.

[theflyingbrick]

i think you should scrap it and get a 330 lol sorry mate i havent a clue on this the most modern car i ever owned is my current ovlov lol i dont do modern motors

[Kingsford G]

i think you should scrap it and get a 330 lol sorry mate i havent a clue on this the most modern car i ever owned is my current ovlov lol i dont do modern motors

330? I don`t think so,compared a mint 330 2003year against my ex S70R and it wasn`t even near my cars performance.

[Dave86]

Cheers kingsford unplugged the maf ran much better then went a fitted a new one and as it turns out the 318 is quite quick although I will be getting a 330 soon :-)