Rough Idle and Code 1271

[hamann318is]

I've been having a few problems with a '91 318is.

The idle from a cold start sometimes struggles, and if I don't put some throttle on, the motor will die. However, I only have to keep the throttle on for about 10-15 seconds before the idle maintains around 850rpm. After this point the motor behaves normally. This is after a quick cleaning of the ICV, which I'm going to guess probably needs a bit more of a cleaning. Any thoughts? I'm very confident that there are no vacuum leaks, the hoses are all only a couple of years old and look almost new.

If I let the car idle for a bit, the car throws the Check Engine light. The code that I'm given at start up is 1271 (Ignition Coil 1). The plugs are nearly brand new, and I had the coil pack out a few months ago, and it appeared to be all right. The plug wires have never been changed, would this seem to be a culprit of these sorts of problems? What's the general consensus about brand of plug wire? Also, what else should I be on the look out for based on the 1271 code?

Thanks in advance!

[lordofthewaters]

1271= "Break or short in the final stage ignition wiring." So I'd start at the plug wires.

[hamann318is]

Are the Bosch wires available at typical auto parts stores all right?

[lordofthewaters]

I suppose they'd be servicable enough. Never bought any wires from NAPA, Autozone etc for my E30's, but if they're Bosch they should be the same.

Autozone's Offerings

Cheaper Here Though

[hamann318is]

I just updated the wires with some Magnecor ones, and it's still throwing the code. The car feels great though -- the idle is perfect and there is no more check light, so is this really a problem?

[lordofthewaters]

Nope. Disconnect the + battery cable for a couple of hours and I'll bet you don't see the code again. Of course after doing that it may run a little rough while the ecu re-learns everything. Or at least that's how the M20's do. I don't know if the M42's work the same way or not.