Question about 2002 Pontiac Grand Prix

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I have a code of lowair flow egr valve and have changed to valve and cleaned the throttle body housing with cleaner. servie engine light still comes on with the same default but not all the time.

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Hello! This is a somewhat common issue where there is an excessive buildup of carbon in the EGR port in the upper intake manifold.
This is the EGR Valve as removed from the engine:

i have a code of lowair flow egr valve and have - 52a1105.jpg
On your vehicle, you will notice that the flexible tubes are held in place by one bolt each. If you remove these tubes from the engine side only - you will be able to clean inside the port that they connect to. I have had good luck using a parts cleaner that any Chrysler dealership sells - it makes short work of carbon build up. Once you have the ports cleaned out - reassemble the EGR tubes to the intake. Be sure to get them seated fully before you tighten them back down.

Hope this helps and good luck!

Posted on Sep 25, 2009


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I have a 1999 Protege 1.6L with 93,000 miles. And a
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When my light came on, I got the EGR code read out at Advance Auto ($0). I googled 'Mazda EGR' and found this is frequently due to carbon buildup in the throttle body. It seems the carbon restricts the flow from the EGR, which then calls for a more open valve, and the error code is "excessive flow". Go figure.

Very easy to disassemble throttle body (just check to see where the EGR line is attached to the intake air path, just prior to injector assembly). Sure enough, a clump of carbon around the EGR port in the throttle body. Cleaned it up with a paper clip, Q-tip, and carburetor cleaner. Total cost < $3.
Cleared to code. No light on now, car runs fine.
If your "EGR VALVE" is bad,
you can get one cheap at the url below, and they take Pay-Pal.
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This will cut fuel to the injectors if not working properly.
Also replace the engine coolant "Thermostat",
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You can pick up both at Auto-Zone for about $35.00.
This fixed our 1996 model. The 1999 model was fixed by replacing the
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Hope this helps.
"Catch me on the flip"

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