Finding and cleaning EGR valve on 1998 Mercury Sable.

What i the exact code number being set?

Don't have the receipt in front of me, but it was low flow EGR, I think P0401

That's not a dirty EGR valve. That's either a bad DPFE or a plugged EGR passage through the intake.

Thanks. So I could clean it out and/or replace the DPFE? How to clean it? I think I know where the EGR is located - driver's side back of engine, right on top like a mushroom. Not sure where the DPFE is.

Differential Pressure Feedback EGR sensor also called a pressure transducer. They fail by the hundreds.

Ok, so what do I do next?

Well, if you don't want to get it diagnosed properly, I'd try a new DPFE

What about the cleaning? I've seen responses suggesting wire insertions and chemical breakdowns (B-12). I'd like to do this myself because it seems so simple, as is buying a new DPFE. I think I should do both, no?

BTW, I've gotten the same response before - replace the DPFE. This just doesn't seem to fix the problem. If there's carbon buildup, then I think it should be cleaned out. How to do this is the question. With a clothes hanger or with B-12 or something like it. Hey, I don't know what I'm doing, and that's why I'm here. There's mention of gasket replacements, throttle body cleanouts, hose replacements, etc. I'd just like a straight answer.

I've given you one. It's your choice if you want to listen.

Thank you and I meant no insult. I just can't wrap my head around a carbon build-up problem and a sensor problem. Could it be that both need examination? I'm just trying to avoid future repairs. Again, I thank you.

I've repaired this code hundreds of times. The DPFE will cause a PO401 80% of the time on a Ford.

So, I removed the throttle body and found a mountain of carbon blocking the EGR passages. Every single intake was clogged. After a thorough cleaning, the light stays off and the engine continues to run fine.

It just makes so much more sense to clear out a passage than to replace a detector valve. After all, which builds up gunk and fails as it was designed to first?

It's easy to remove the throttle body and clean out the plate and the passages. Believe me, this is the first time I tried to do it and it was easy with a $20 Kmart socket set.