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View Full Version : Bad idling, miss



Bigfatts
10-21-2010, 04:45 PM
I have a '94 SC. Stock except for a CAI. Since I bought it it's had an occasional miss. It seems to be getting worse and it can make the idle very rough. I just replaced the plugs/wires last oil change (Autolite Platinum and Taylor Thundervolt wires) with no change. I pulled codes and came up with a 214- Cylinder Identification Circuit Failure. That's the only one that came up. Any idea what it means? Something to do with my problem? Any input is appreciated.

Bigfatts
10-22-2010, 12:18 AM
Forgot to include that my fuel economy is very poor lately, averaging 16-18 the last few tanks.

S_Mazza
10-22-2010, 09:47 AM
Cam or crank sensor may have kicked the bucket. You can run without the cam sensor, but not the crank sensor. Try unplugging the cam sensor (but make sure the clip doesn't contact the belt) and start the car. It may take a few extra tries without the sensor. If it runs well, then you have found the problem. If not, then maybe it's the crank sensor. That can be tested with a test light and some long pins to backprobe one of the connectors.

I am not sure about this, but there is also one other thought floating in my mind, which is that it might also be related to a faulty ignition module (the gray box on the passenger side fender). But I would check the other things first.

Mike8675309
10-22-2010, 10:07 AM
CID is Cam Sensor. you should clear the codes and drive the car again and see if that one comes back. If you can describe the miss as a like a significant hesitation, almost like the car bucks, that can be indicative of a bad CAM sensor.

One test you can use to verify before replacing is to physically disconnect the sensor harness connector. With the connector disconnected, the car may require 1-5 attempts as without the sensor the EDIS module will guess at when #1 is on compression. It has a 1 out of 3 shot of guessing right.

If with the connector removed, the miss goes away, then you should be safe to assume it was the cam sensor.

TbirdSCFan
10-22-2010, 01:42 PM
Ensure that your plug wires are fully seated.. there should be a faint snap when they are pushed onto the plugs. A bit of plug boot grease will help out.

EatonEmployee
10-22-2010, 09:03 PM
mine has been doing this too but only intermittently since the dyno run. It did it when I tried to chip it as well. I have a 93 AOD with 98k. If I find the fix I will post it. I am probing. Is yours intermittent as well?

Bigfatts
10-23-2010, 11:44 AM
Thanks for all the tips guys! I will definitely check the sensors. Yes, it is a come and go problem, mostly when it's good and hot. As for the plug wires, they are god and tight as they should be.