Question

What does Code p1404 for a 1999 Cadillac Seville STS 4.6L mean?

Answer 1

1404 is a code for the EGR valve. This code indicates the pintal in the egr is not moving properly. This could be caused by a couple things. First, the egr port could be blocked, then when the egr valve opens the map sensor doesn't sense a pressure change and will set the code. Cleaning the port can solve the issue. The other issue is that the pintal on the egr valve could be sticking. Sometimes you can clean it with carb cleaner to resolve the problem.

Answer 2

P1404 CADILLAC - Exhaust Gas Recirculation Closed Position Performance

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