[rjw]

car is 2006 330i

My car is idling rough. It starts fine and seems to have reasonable power. Gas mileage hasn't changed, but low rpm acceleration seems sluggish.

I am waiting for my obd2 to usb cable so I can use inpa to troubleshoot.

In the interim, I scanned with an Innova 3030g and got the following codes

P0306 cylinder 6 misfire and P0171 and P0174 system too lean for banks 1 and 2

Battery was replaced a year ago (napa).

The oil filter housing was leaking, so I removed it. The alternator is totally saturated with oil, so I removed it as well.

Spark plugs were changed at 80k miles (81k on car now) along with 1 coil.

When I changed the coil, the supplier gave me one from a 330 ci, but while the rough idle was gone, the ci coil had a spring in the sparkplug end while the oem snapped on to the plug.

They ordered another coil that snapped on like the oem and the rough idel returned??

Any thoughts on all this?

Thanks

[3002 tii]

Sounds like a vac leak. Do a smoke test.

[rjw]

Originally Posted by 3002 tii

Sounds like a vac leak. Do a smoke test.

I forgot that I also had code P2402 related to evap emmision,

I you have a link to how to do the smoke test, please share.

thanks for the reply

[3002 tii]

Originally Posted by rjw

I forgot that I also had code P2402 related to evap emmision,

I you have a link to how to do the smoke test, please share.

thanks for the reply

Without proper equipment not so easy. But at very least take a flashlight and see if any hoses have cracks like near the intake. Here's one DIY for smoke test. If after you've ruled out vac leak (problem relating to air) then I'd look into your o2 sensors (problem pointing to fuel).

[rjw]

thanks....will rig something up

[rjw]

Update:

Had an oil leak from oil filter housing, so I changed the seal and flushed coolant.

Checked plugs as well and cleaned and swapped vanos valves.

Car idled great at first, then back to rough. Found a bad coil, replaced and now smooth again.

After a test drive, got a P0010 Intake cam sensor problem, so I suspect either the cam sensor or probably the vanos valve.

Will see what comes up after checking the senso and some extended driving.

At least it idles smoothly at the moment and pulls well at lower revs

More later

[rjw]

I pulled the intake cam sensor an it was pretty seriously crudded up. Same as the oil fill which has looked cruddy pretty much from the get go in 2006.

Also took off and cleaned the MAF.

Started car, P0010 gone for now, but I had a maf air floe too low code and engine was hunting just a bit.

Eventually it cleared up and now after a 2 mile run, NO codes related to engine, etc???

When I had the lean codes, my scanner showed stft's up in the 20's. Perhaps the car had to re-learn the short term fuel trims .

Going on a long ride ....will update later.

[rjw]

After several hours of stop and go and highway driving and some serious acceleration, the P 0171 and P 0174 codes are back, but now they are pending as opposed to pending and stored.

Also, the P 2402 code is now stored and pending.

The car runs great, starts right away and idles smooth as silk.

Also, NO SES or CEL light at all. So I am making some progress.

Next up I will rig something up to check for leaks and have a look at the evap/charcoal/pump stuff.

I have the BMW standard tools software installed and should get my usb to OBD2 cable on Monday or Tuesday.

Making some forward progress..happy NOT to see that friggin ses light !!

more as it happens

[JuniorB]

On a cheap scanner, you can watch your 02 sensors on live data. If you have a large variation, it's a good indication that it may be on its way out. Evap codes are pretty straight foward but a smoke test is the only way to tell. Also look into a bad fuel cap, it will not pressurize the system with a bad cap. I had evap codes on my truck and read that a smoke test is the only real and sure way to find it. It ended up being a nipple on the gas tank. Which required replacing the tank. Check your intake pipe after the maf to throttle body for connection. For $100 get the test.

[rjw]

thanks for the reply...I'm waiting for my cable and looking into diy options

thx

[TheBigChill]

Smoke test. I made a contraption for $8 at the hardware store and used a $1 cigar. Found a leak in less than a minute. Hit the easy button, man. Here's my video after checking the leak with leak detector (soapy water) and a bike pump. For my original smoke check I just propped the throttle plate open with a tool (not one small enough to fall into the manifold) and blew cigar smoke until I couldn't blow anymore. It only takes 1 or 2 psi to find a intake tract leak.

[rjw]

Thanks for the reply and video.

Nice to see creativity at work. I've seen a cigar test , paint can smoke machine and more, but I'm still waiting on the cable so that I can run the bmw standard tools software.

I have more than a few fish to fry with respect to current problems with my car, so in the meantime I've been working on other problems.

Today, Besides fixing my wwasher pump leak, I bought a new gas cap. On the way back from the dealer, car began shaking again and I got a misfire on cyl 1 code. Turned out that 1 of my ngk spark plugs with only 5k miles on it went bad ??

Engine was shaking, but replacing the plug returned things to smooth.

I've only put about 10 miles since the gas cap and plug, but so far no engine codes at all ??

Wishfull thinking, but perhaps my P2402 evap related problem is resolved??

more later

thanks guys for the feedback

[rjw]

latest update...

Took her for a 50 mile ride, mostly highway driving. No codes until I got stuck in bumper to bumper, then only P0174.

Lean on bank 2 , which I've read means cyl 4,5 and 6.

So, I am thinking that my vacuum leak is probably closer to the back of the engine??

thoughts?

side note: mpg was 30.9 while cruising between 60 and 80 mph...not sure how that compares??

[markv123]

I had a leak bad CrankCase Valve Cap that I had to replace.
If you check my profile you will find a thread that I made regarding it and it solved my issue.
Hope you sort it all out.