EGR Leak

TurboWagon · Post by **TurboWagon** » 07 Jan 2011, 00:50

I've been getting code 1-5-4 which means EGR leak, is this just a vacuum leak, or does the entire unit need to be replaced, I've taken the manifold off to get at the knock sensors, so I figure now's as good a time as any.

icelandic · Post by **icelandic** » 07 Jan 2011, 04:32

It means that the EGR valve is letting some exhaust gas to go into the intake when it shouldn´t. The EGR valve acts on a open or closed cycle, and is commanded by the ECU. It should be open only under certain conditions. If it is leaking, even at idle, it means it is not shutting off completely as it should. One of the symptom is that at idle you will have some small oscilations in RPM, if you listen carefully.

You might try to clean the EGR up, by letting it soak in carburator cleaner overnight, and removing all the crud that gets accumulated inside it. After it is totally cleaned up, you can check if its is ok by trying to blow thru the large opening that connects to the exhaust pipe that goes to the back of the engine. If it is ok, it will not let any air go thru. However if you can blow some air thru it, even in small volumes, you will have to replace the valve, as it is not serviceable. With some luck, it may be just accumulated crud that is not letting proper closure.

Do not forget to clear the hole where it attaches to the intake manifold.

TurboWagon · Post by **TurboWagon** » 08 Jan 2011, 01:50

Thanks for the help, I'll let it soak hopefully won't need a new valve, those things are expensive!