CEL flashing
#1
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CEL flashing
Last night as I was sitting in the drive thru of my favorite chicken joint my cel came on flashing. I was at idle and had my ac on. So I cycled thru the engine sensors on the dicu and no readings were abnormal. I shut the ac off and the light went out. Turn the ac on and the light came back on flashing. So when I was leaving I wanted to further diagnose the issue. Turned the ac on and waited for the light to come on at idle, when I got it, I left the parking lot and almost immediately the light went out. Seems that it is only a idle. I can't get to an OBDII reader today. You guys think it's an ac pressure switch sensor or a possible miss fire? I am running pretty rich at idle an having warm start up issues. Taking It to get tuned after header install.
Current mods:
232/234 cam w/ dual springs
msd wires and ac delco plugs
De-screened maf
25% ud pulley
Current mods:
232/234 cam w/ dual springs
msd wires and ac delco plugs
De-screened maf
25% ud pulley
#4
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On most cars when the ac comes on it advances the throttle slightly so the extra load wont bog the engine. If the caddy is the same way and you are already really rich this could cause the light. I believe the flashing light is missfires if I recall.
#7
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So because you've never heard of something means it's not true? Multiple misfires are the most common cause of a flashing CE light. They are not the only cause. It's usually a problem that is allowing unburnt fuel into the exhaust. Failed/damaged injectors, ruptured fuel pressure regulators, bad valves, low compression....all will cause high O2 sensor voltages and flash the light. If the light is flashing, there is a high probability of permanent damage of some type. The catalytic converter is usually the first thing to go.