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Fuel cleaners for EGR systems

Are there any fuel cleaners that will work to remove the carbon build up in the EGR system. I had the codes read and it was PO33 and was told the EGR isn’t opening or closing. I have a 1993 Ford areostar and was going to just replace the EGR valve myself but I can’t even see it from under the hood or from inside behind the doghouse. How much would a mecanic charge to fix this problem before it leads to more serious problems? HELP!

One of these will show you the way:,14400108/shopping/partTypeResultSet.htm It’s usually necessary to remove the EGR valve to clean it.

I seriously doubt that an EGR that is not flowing will lead to any more serious problems, other than perhaps failing its emissions inspection due to the error code.

You will get slightly higher NOx emissions if it does not flow, and possibly slightly lower mileage (possibly).

I got one working on a '91 Volvo by disconnecting the line at the intake manifold and pouring SeaFoam cleaner down the tube and letting it soak all night before starting the car. I’m sure there is still plenty of crud in there, but it is better than it was before.

After much anyalizing of the EGR system I’ve come to the conclusion that Seafoam just may clean the carbon build up out of the EGR valve. After all, the EGR system is designed to recirculate gas that hasn’t been burned, so apparently the gas must go through the EGR valve giving the Seaform 2 chances of doing the job. I’m on my first can of Seafoam now. I added it to 20 gallons of gas. If it doesn’t do the job I will add a can to 10 gallons of gas. $20 sure beats what it would cost me to have a mechanic take the EGR valve off and either clean the carbon out or replace it. I also added a half can (8oz’s) with an oil change and 1-2oz’s through the pcv valve. I’ll let you all know how it turns out. Wish me well.

After all, the EGR system is designed to recirculate gas that
hasn’t been burned, so apparently the gas must go through the EGR

Not quite. The EGR causes a small percentage of already burned exhaust to get recirculated back into the intake. The goal is to dilute the incoming air/fuel mixture a bit to prevent NO2 from forming.

Nitrogen and Oxygen only combine at high temperatures. The high temps that normally occur in a combustion chamber can be reduced a bit if the air/fuel mixture is diluted with some “already-burned-exhaust-gases”. The result of those gases means lower combustion temperatures and lower amounts of NO2.

So the Seaform that you’re adding to your tank isn’t doing anything for your EGR valve.

You don’t have to do anything but break some of the carbon off if it is totally blocking the passage to the EGR valve. Usually it’s an easy job even if you have an egr valve that can have carbon on it. Carbon isn’t the only problem an EGR valve can have. Two to four hundred dollars for a shop to fix it and maybe a few hundred more if another part of the system is causing a problem.