CEL Flashing Repeatedly when Pulling Codes
09-14-2012, 06:49 AM
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CEL Flashing Repeatedly when Pulling Codes
First post here and I have searched for the answer for this. I hope I haven't overlooked it.
I pulled the codes when I got my truck and had a 14, 21 and 42. The truck runs great in open loop, but once warm it loses all power. I knew the truck was missing the Cat and O2 sensor so I had them installed. After installation, I tried resetting the codes by pulling the EF1 fuse. When I used the paper clip to reread the codes because it is still running poorly when warm, I am getting a repeated flashing of the CEL (no codes, but constant flashing).
First, what does the constant flashing mean?
Second, anyone have troubleshooting tips for the poor performance when warm?
I pulled the codes when I got my truck and had a 14, 21 and 42. The truck runs great in open loop, but once warm it loses all power. I knew the truck was missing the Cat and O2 sensor so I had them installed. After installation, I tried resetting the codes by pulling the EF1 fuse. When I used the paper clip to reread the codes because it is still running poorly when warm, I am getting a repeated flashing of the CEL (no codes, but constant flashing).
First, what does the constant flashing mean?
Second, anyone have troubleshooting tips for the poor performance when warm?
09-14-2012, 07:06 AM
#3
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A constant flashing means no codes.
Therefore, your problems are mechanical and not electrical/sensor based.
Start with the basics...
Fuel
Air
Spark
Combustion
Timing
Therefore, your problems are mechanical and not electrical/sensor based.
Start with the basics...
Fuel
Air
Spark
Combustion
Timing
09-14-2012, 07:25 AM
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Well, it could be electrical/sensor, just not the sort of failure that the ECM is set up to detect. (After all, spark is electrical.)
I would check the timing first. Easy to do, and timing-off could cause your symptoms. You'll need a very basic timing light, but they are cheap and necessary.
I would check the timing first. Easy to do, and timing-off could cause your symptoms. You'll need a very basic timing light, but they are cheap and necessary.
09-14-2012, 07:45 AM
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Well, it could be electrical/sensor, just not the sort of failure that the ECM is set up to detect. (After all, spark is electrical.)
I would check the timing first. Easy to do, and timing-off could cause your symptoms. You'll need a very basic timing light, but they are cheap and necessary.
I would check the timing first. Easy to do, and timing-off could cause your symptoms. You'll need a very basic timing light, but they are cheap and necessary.
Now I agree that it can't tell whether an individual spark plug is working, but the system is controlled by the ECU and would throw a code if it's not working. In fact the code for a 22re is 12 by the way. I just went through this with a bad signal generator in the dizzy.
Last edited by snobdds; 09-14-2012 at 07:46 AM.
09-14-2012, 09:22 AM
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Just as an example, if the spark plug gap is wrong, I'm pretty sure the igniter will still produce the IGF signal even though the spark plug does not actually fire. (Same with a broken plug wire.) So no codes. www.autoshop101.com
The codes are designed to tip you off to failures that are difficult to find with the usual methods (like an igniter that is failing to produce the ignition pulse). But they don't let you off the hook for ordinary diagnosis. As snobdds said, fuel, air, spark, combustion and timing are needed, they're all (partially) electrical, and none of them throws a code every time they're off.
The codes are designed to tip you off to failures that are difficult to find with the usual methods (like an igniter that is failing to produce the ignition pulse). But they don't let you off the hook for ordinary diagnosis. As snobdds said, fuel, air, spark, combustion and timing are needed, they're all (partially) electrical, and none of them throws a code every time they're off.
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