Topic: ECM Removal High Idle 82
in Forum: C3 Electrical
Just wondering if the driver's seat has to be removed to get the ECM out?
I'm getting that high idle intermittently now. Some days it is just fine.
I have observed the failure with the air cleaner off and the linkage is not binding and I'm not really buying the leaking bushings on the Throttle bodies. There is free movement and when sprayed with starter spray no change in idle. I know it is a common problem with 82s but, do not think it is my main problem. I am happy with the vacuum system. I have checked the wiring to the O2 sensor and tried several with the same code 13. So, I want to look into the ECM for connections and wiring. It is intermittent. A vacuum leak would not be. A crack or solder joint failure on the PC board could do this kind of thing. I think anyway. Since it cooled off from the summer temps, I have had a string of days that it runs correctly. Starts at 1200 rpm then slowly (a couple of minutes) drops to 700-800 rpm. Past few days the start is up to 1500-2000 rpm and stays there. I'm thinking the ECM is worth a look.
Thanks
Keith
Nobody ever waves when I'm driving the Explorer.
K Woody
The ECM is located in the battery compartment and is a PITA to get to. Remove the battery and then poke your head into the compartment and you will see the ECM bolted to the bulkhead directly behind the drivers seat. I used a mirror to locate the 4 screws holding the ECM to the bracket. I think the screws are 10mm and they are difficult to get to but possible. Removing the drivers seat may make it easier for you to kneel on the floor with your head poking down into the battery compartment but it AIN'T GOING TO BE EASY OR COMFORTABLE EITHER WAY. There are 2 large connectors which plug into the side of the ECM closest to center of the car. The connectors have lock catches on them so study the way they connect before pulling too hard to get them off. I'm at work now and don't have access to my pics but if you need pics I think I have some on my home machine from when I had mine out.
Lifetime Member
The performance chip is most likely an EPROM IC. It would go in the ECM replacing the original IC. I can see the ECM. It does look a bit like a contortion to get it out. I'll try with the seat in first. Thanks Chip.
I've been working too much on the garage and not enough on my baby. Ha
Nobody ever waves when I'm driving the Explorer.
K Woody
CODE 13
Trouble Code 13 indicates that the exhaust stream oxygen content sensor (O2 sensor) is not responding as expected. When cold, the sensor is 'biased' by the ECM to about 450 millivolts. Before it warms to at least 600 deg F (315 deg C) it acts as an open circuit and when the ECM reads it, it reads the 450 mV bias. The ECM expects the sensor to warm in a short period of time and begin sending its own voltages.
The conditions for setting this code are:
•
Engine running at least 40 seconds and•
No code 21 or 22 (TPS errors) present, and•
Coolant temperature is at least 118 deg F (48 deg C), and•
O2 sensor voltage not fluctuating (i.e. steady between 350 and 557 mV), and•
TPS signal indicates above idle (over 6%), and•
All the above conditions met for more than 8 secondsTypical causes for this code include:
1) Defective or degraded O2 sensor
2) Deposit contaminated O2 sensor (running leaded fuel, RTV silicone deposits etc.)
3) Corroded/defective O2 sensor connection
4) Defective sensor ground circuit
5) Defective connection at ECM
6) Defective ECM
Lifetime Member
