$500 in parts- now have stumbling issue

[xwill112x]

+1 with cap and rotor

[SpecM]

I don't see how mis adjusted valves could cause this

I would be concerned about that cap/rotor, that's more scoring than I've seen on 20k units, much less 1k ones.

[bimmerboy12]

Pull out the brake booster. If it dies, chances are there's a vacuum leak elseware. Easy way to rule it out man.

OK, pulled the brake booster vacuum line. Started sucking air like a bitch and idled horribly but did not die. Plugged it back in and resumed to normal shitty idle.
I have now done everything you guys have suggested. Please don't tell me its time to take it in to the stealer...

[Mitchel]

Pull out the brake booster. If it dies, chances are there's a vacuum leak elseware. Easy way to rule it out man.

[bimmerboy12]

Suggestion - I see a new Valve cover Gasket on your list did you replace the 4 small rubber arrow head pieces. Is a very small vacuum leak possible to cause this just at Idle?

Good Luck
Keep your hair

No Check Engine Light. Car stumbles when cold and when hot, but differently.

Yep, replaced the four "D" shaped rubber pieces, old ones were hard as a rock.

I will try pulling the booster hose to see if the car dies, but this was in an area that was untouched and all lines were checked for vacuum leaks.

Also, I put this cap back on without the black cover, and there was no arcing anywhere as was seen on others caps on this thread. There were no carbon tracks inside the cap.

I am now thinking about my valve adjustment. All the valves were right on, could they have moved afterwards causing this issue?

hair is in grave danger.

[dj01540i6sp]

Suggestion - I see a new Valve cover Gasket on your list did you replace the 4 small rubber arrow head pieces. Is a very small vacuum leak possible to cause this just at Idle?

Good Luck
Keep your hair

[Mitchel]

#1: Why haven't you pulled the code resulting in your CEL yet? You're getting a check engine light.

#2: When you pull out the brake booster hose, does the car die?

This sounds like a vacuum leak to me. You'd know if this were a timing issue even if it was cold.

[Naplm00]

my afm failed one random day at a light

shit happens ?

[bmwpower]

That's quite normal as you're transferring spark across those contacts. But now that you have them off, take some fine sandpaper and lightly sand the carbon off.

I think what other people were referring to were carbon "tracks" in other places inside the cap, like from an adjacent contact to another.

[bimmerboy12]

OK, took the cap and rotor off and as you can see there is severe buildup on the contacts on the cap and rotor. notice the metal burrs rolled over on the cap contact. This is after installing brand new cap and rotor about 1000 miles ago this past summer. Both are Bosch and bought at Bavauto.
Your thoughts???

[bimmerboy12]

i would swap in a known good AFM, i had issues like this and that was the culprit

So the AFM randomly went out when I put in all these parts? Seems unlikely. I will remove and inspect the cap again and look for carbon tracks. I have also seen some cases on here where this type of idle issue can happen after a valve adjustment. Should I go back in and check the valve clearance?

[AndrewBird]

A lot of times the material they use to make distributor caps will have too high a carbon content. What this does is provide a ground, bypassing flow through the plug wires. Look carefully at the cap and see if you can find any small thin black lines (carbon tracks) running through it anywhere.

[Naplm00]

i would swap in a known good AFM, i had issues like this and that was the culprit

[bimmerboy12]

Ok, i had to revisit this thread to see if any of you found the source of this problem. I inspected my wire/cap area in the dark and saw no arcing. I can't tell you how pissed I am about this. Does anyone have a spare used cap that worked? I would rather pay for the shipping of a used cap then buy a new one that may still be faulty.
Seriously. Its getting f#$%ing ridiculous how long this problem has been going on.
Brian

[dr.strangelove]

i'm with you there. i have been having the same issues.