318ci Stuttering, running bad

[SanderVdW]

Hi guys,

So I've got a nasty issue I've been dealing with for the better part of the last few months. Sometimes though it seems to be running only on 3 cylinders, shaking and very hesitant throttle response and slow rev building up.

Exact symptoms I see, don't know if they're all related to the same issue:

1) On cold startup, the engine shakes and stutters and drops in rpm to about 500 for about 20 seconds, after that it runs fine.
2) It's throwing the misfire on cylinder 3 w fuel cutoff code.
3) Intermittently the engine very shaky, hesitant and very slow in rev build-up, you can clearly hear its running on only 3 cylinders (probably why the misfire code is thrown). When it runs like this, there is a very distinct clicking noise from the valve cover gasket, I would say around cylinder 3 (hydraulic valves). Here you can hear symptom nr 4 very clearly: <font color="#000000"><span style="font-family: verdana">
4) There's a lot of carbon exiting the exhaust along with the water.
5) There's a small hissing noise when the throttle is opened which lasts only about 1 second when revving.
6) When I remove oil filler cap while engine is running there's a lot of pressure pulses, don't know if that is normal.

So far I've excluded:

-Bad ignition coils
-Bad injectors
-Bad spark plugs
-Bad MAF sensor
-Bad O2 sensors

So far I've done:

- I've changed the valve cover gasket cause that was leaking oil
- I've cleaned the secondary air pump system, which was full of carbon build-up
- I've changed the fuel filter
- I did a Liqui Moly engine Flush and now added a quart of Dexron III to the new oil, hoping this would possibly fix the hydraulic lifter problem (if there is one)

My thoughts its a mix of a problem with one or more of the hydraulic valve lifters on the exhaust side, which explains the ticking noise and engine running so roughly (intermittently) and a bad CCV, because otherwise why would there be so much pressure exiting the filler cap, this should go straight through the CCV.

Any further ideas?

[MarcoZandrini]

The first step in diagnosing a problem is to scan the engine computer (DME in BMWspeak) for codes. Throwing parts at the problem wastes money, doesn’t fix the problem and it angers the BMW goddesses. Get the DME scanned and post the codes.

[SanderVdW]

I scanned the car buddy, as I explained in my description I get the "misfire on cyl 3 with fuel cutoff" code, dont remember exactly which P code it is, but thats irrelevant.

[MarcoZandrini]

Sorry, old age!! A misfire can be caused by a myriad of things. I assume (me bad) that when you write “I’ve eliminated following” you’ve either replaced or swapped the parts listed. Please confirm.

You write that you have pressure at the oil fill cap. There should be a slight vacuum there. All modern BMW engines require the crankcase to be under a slight vacuum. Pressure is definitely odd. Is the CCV original? Also, lifter ticking could be caused by oil issues. What oil do you run? What filter brand do you install? How frequently do you change the oil and filter?

[SanderVdW]

Hey man, thanks for the replies, don't worry about the mistake. Yes, all parts are either new or changed in between cylinders. I haven't taken a look at the wire loom connectors for the coils and injectors, but that would not explain why the car runs roughly on startup, after 2 seconds runs perfectly and after a minute or so runs only on 3 cylinders.
This is a video I took today:

https://youtu.be/6VNbTbDr170

I also checked compression today and I have around 200psi on all cylinders, including cyl 3.

I do have a slight vacuum on the oil filler cap, but also some positive pressure pulses, is that normal? Could that maybe indicate a blocked CCV? I have no idea if its original, I bought this car second hand as well.

The oil is 5W-30, but since I bought the car I did a Liqui Moly engine flush and replaced the oil, as well as the filter, with Bosch one. Then added Wynns hydraulic valve additive to the new oil, also 5W-30.

Something is making the engine running on 3 cylinders, but only intermittently. I can't stress this enough: on cold startup the engine drops in rpm to about 500 and is shaky and runs rough, then after 20 seconds runs perfectly fine and then after about a minute and a half cylinder 3 dies and this horrible ticking noise comes with it. And I have absolutely no idea why this happens

[MarcoZandrini]

Has to be something mechanical. I’m thinking a lifter is acting up. This could be caused by a lifter that’s “gunked up” or a problem with oil supply to the lifter. I bet the lifter is gunked up. It may take a while for the gunk to dissolve and the lifter to act normally. What you could do is substitute a quart of Dexron3 or similar ATF for a quart of oil at the next oil change. ATF is highly detergent. In fact, you could use non-synthetic high detergent oil and ATF for 500 miles and then change over to synthetic. Let me add that the oil filter should be made by Mann as it’s the supplier to BMW. The Bosch filter may be fine but there have been horror stories of aftermarket filters disintegrating in the housing after 7000 miles. Also, what brand of oil are you using?

[SanderVdW]

What you could do is substitute a quart of Dexron3 or similar ATF for a quart of oil at the next oil change

That's exactly what I did and also put in some Wynns hydraulic valve lifter cleaner. So what you're telling me is that I need to be patient and just run the car for as many miles as possible, hoping this will solve it?

[MarcoZandrini]

Yeah, it could be the lifter is badly gunked up. But, why aren’t any other lifters acting up? In the end the lifter could be bad. Run the car and see what happens.

[SanderVdW]

But, why aren’t any other lifters acting up? In the end the lifter could be bad.

I have no idea, I'm hoping it will be gunked up. If it would be bad or broken it would not run fine sometimes, right? I would imagine that it would run badly all the time then.

[MarcoZandrini]

Most likely it would but it might be failing only when it’s cold.

[SanderVdW]

Something doesn't add up with a bad or gunked up lifter. If this were the problem then the engine would run badly all the time instead of running badly the first 50 seconds of cold startup, to then run perfectly fo 40 seconds to then lose one of its cylinders. It does that exact routine everytime. If it were a bad or gunked lifter, it would just run badly from start, no?