I tried the stomp test for the first time at the weekend and it reported 1222 and 2222 which is lambda control #1. I did some looking around and these errors look like a catch-all for fuel/air mixture problems and could be caused by lots of things.

I had a rough idle a while ago that looked like IM gaskets but that has mysteriously disappeared and the idle is OK (even in cold weather when it used to be terrible). My O2 sensors look like they've been there a while. I get occasional EML errors on cold start up, could that be related? This has wild goose chase written all over it.

I want to avoid repairing stuff that isn't broken as i'm expert at that! Anyone have a good plan to diagnose this, maybe starting with the cheapest/easiest option first? Cheers, Nick

Nick,

Have you changed out your fuel filters? mine were horrible, seemed to be the originals from the factory. The difference was night and day after I changed those out.

No I haven't looked at the filters yet, probably needs doing whether or not it's the cause of this problem.

Do I need 2 x #8s? http://bmwfans.info/parts/catalog/E31/Coupe/Europe/850Ci-M70/RHD/A/1990/december/browse/fuel_supply/fuel_supply_double_filter/

Yep. Also, since your there anyways, might want to replace the hose, too.

I tried the stomp test for the first time at the weekend and it reported 1222 and 2222 which is lambda control #1. I did some looking around and these errors look like a catch-all for fuel/air mixture problems and could be caused by lots of things.

I had a rough idle a while ago that looked like IM gaskets but that has mysteriously disappeared and the idle is OK (even in cold weather when it used to be terrible). My O2 sensors look like they've been there a while. I get occasional EML errors on cold start up, could that be related? This has wild goose chase written all over it.

I want to avoid repairing stuff that isn't broken as i'm expert at that! Anyone have a good plan to diagnose this, maybe starting with the cheapest/easiest option first? Cheers, Nick

Try taking off your O2 sensors, clean them and reseat. Check the wires. See if that fixes it first. It could also be your cats starting to go bad.

I replaced the fuel filters. The old ones were stamped "BMW 2001", so I guess that's the last time they were replaced. It hasn't made any noticeable difference but it was probably a worthwhile thing to do.

Ahmed: i tried to shift my O2s but couldn't even get the tool (i bought a socket with a slot down the side) on the sensors under the car while it was on ramps. I think i'm going to have to take the car to somewhere with a lift. Has anyone managed to shift their O2s by grovelling under the car?

I noticed today that there was a fairly loud sucking sound coming from one side of the engine that I haven't noticed before. I pulled at the inlet manifolds to see if that made a difference and i don't think it did. The noise went away as the engine warmed up. Is a sucking sound a symptom of leaking IM gaskets?

I'll stop blethering on now....time for more curry and beer... I've got some Old P in the fridge (http://www.theakstons.co.uk/ales/bottled/oldpeculier.html). Real beer. For all you Californians, Bristol Farms sell it - but be warned - it's evil :shifty.

...I noticed today that there was a fairly loud sucking sound coming from one side of the engine that I haven't noticed before. I pulled at the inlet manifolds to see if that made a difference and i don't think it did. The noise went away as the engine warmed up. Is a sucking sound a symptom of leaking IM gaskets?


...Yes