1994 530i rough idle, cylinder miss?

[winfred]

they probably don't have a bmw reader, a regular code reader won't touch a pre obd2 (95 and older) bmw

. I think the local auto parts store has a diagnostic code reader and will test for free... time to find out.

[Been-Jammin]

After you replace (or before) the gaskets reboot the thing. When my intake was leaking last winter it ran just like yours, check light, the miss, everything. I rebooted the computer and it read that the leak was a "normal" leak and the car ran a lot better for several months until I got to the gaskets. When I had my intake off there was one of them air horns rolling around in there and that could have caused the intermittant miss by blocking an intake port.
Before that after I bought the car it had a real bad miss that I chased with coils, plugs, Injectors only to have the same miss which was "Caused by Nikasil" until I replaced the plug boots...they all checked out with the ohm meter but the new ones solved the whole dilema...40k or so ago.
Also, them specialty plugs can cause strange idle/miss problems, stick with the stocker plugs.
Good luck to you!

Silly Question: How do I "reboot" it? Do I disconnect the battery? (I have the radio codes) I know the battery is located under the rear seat, but honestly, I've never seen it for myself.

[winfred]

you can unplug the computer which is under the black cover on the right side under the hood and not effect the rest of the car, the engine computer should be the one closest to the windshield, unplug for a minute or so and it's done

Silly Question: How do I "reboot" it? Do I disconnect the battery? (I have the radio codes) I know the battery is located under the rear seat, but honestly, I've never seen it for myself.

[Been-Jammin]

whistle is not normal,

Good to know.
PCV Plate/Gasket, etc. on the parts list... Thanks!

[Been-Jammin]

I shut off all of the accessories including radio and turned the AC vent controls all to the left. Pulled the key out entirely, put it back in and 5 stomps on the accelerator. The check engine light blinked, stayed on and then went into a pattern: .5 sec on, 2.5 sec off, 2.5 sec on, 2.5 sec off. It just kept repeating that exact pattern. I then held the pedal down for 10 seconds. Turne ignition off and repeated. This time it showed 1444. All Ok.

So will wait until tomorrow morning and see if the check engine lght comes back on and check the codes after that.

[Kalevera]

Ah, I'd still take it to a good indy and have them stick it on a machine. If the check engine light was ON, there's a stored code.

http://www.iaibmwsp.org

There should be someone in there who can read the codes for you. Local auto parts stores...hehe...well, they're usually a bad place to go for anything BMW.

best, whit

[632 Regal]

any vacumme related ill effect will result in the O2 code...which is irrelivant at this time. Either pull the computer out of the box or disconnect the battery for like 30 minutes...there is Shoguns reset which involves crossing the cables (after disconnecting them of course) and discharges everything, that seemed to make a greater difference than just disconnecting them.

[Been-Jammin]

any vacumme related ill effect will result in the O2 code...which is irrelivant at this time. Either pull the computer out of the box or disconnect the battery for like 30 minutes...there is Shoguns reset which involves crossing the cables (after disconnecting them of course) and discharges everything, that seemed to make a greater difference than just disconnecting them.

Thanks! I disconnected the computer, which no doubt cleared the codes. It's showing 1444 now. The check engine light only comes briefly when warming up and first hit's the "closed loop" coming out of "warm up" mode. Will have to see how it does in the morning and go from there. I took a 1/2 hour drive this afternoon and nothing unusual, no engine light either.

I've ordered all the intake gaskets, etc. including plug boots so should have a nice weekend project coming up. I'll have the leakdown tester by then as well. I figure it's worth it at this age/mileage if nothing else to clear my head of worry.

[632 Regal]

Does it still have the miss or did that smooth out some?

Is there a code from the CEL during warm up?

1444 = no codes

[Been-Jammin]

Does it still have the miss or did that smooth out some?

No change in roughness, idle or running. Still has a miss...
Going to check for codes in the morning after the drive to work.