Hello: Being told by local shop (not dealer) that my fault codes for lean are largely result of leak from EGR. PLUS: the EGR is not working at all. Apparently it uses electric motor, not vacuum like the old days, and the price is $600+ USD. Has anyone else had a failure of this on X350 with 130K plus miles on it? Would not want to put one on and have no improvement. The shop says they will put it on and calibrate it to my ECM even if I buy it elsewhere. Just so I sort of understand this...some small bit of exhaust is drawn from manifold and introduced back into intake under specific conditions, right? If a leak develops on the intake side, then you have a lean condition and the classic p171 and p174 codes. Am I still sort of on right track? If the valve actuator motor is not working, the thing would be stuck in closed or open mode? Car runs smooth and fuel economy is excellent. Long term fuel trims are running rich and short terms lean with resulting stoichiometry (how DO you spell that?) in range. And where exactly IS the EGR on a 4.2L 04 not supercharged? Thank you.

 

You're on the right lines

EGR reduces in-cylinder temperatures and NOx, and improves MPG.

Whether your code(s) is/are due to EGR I can't say and as it's "awkward" (read: hard) to change I'd be tempted to try to find out more but not sure best way to do that on your car.

If it's where I think it is then do any other related work at the same time. Be glad it's not SC as then it's a lot more work!

 

Not sure if this is any help, but my EGR problem started with code P0405. I was conducting the appropriate Workshop Manual Pinpoint Tests and noticed immediately that a wire to the EGR Valve connector was broken; fixed it and problem went away. Someone more informed may correct me, but I would have thought an EGR Valve fault as debilitating as yours would throw an EGR-specific code?

The EGR is attached to the Throttle Body in this NEXT picture:

 

Throttle Body with EGR

 

This is helpful, thank you. FWIW, there is a 05 radiance XJ8L at a local car lot I am in love with but need to sell mine first and that won't happen till CEL is out! Anyway, my car has intake leak at either PCV valve or EGR or BOTH! Still trying to sort that out with person who "diagnosed" it with their smoke tester. PCV is a $40 item while EGR is more like $315. I don't like throwing money around experimentally. I can put in a PCV myself but EGR needs some kind of "calibration" with ECM. Has anyone done that or do you need a special computer interface for that? Thank you.

 

What are your codes and what symptoms do you have?

I have just looked up EGR problems and it does not sound like that at all.

https://www.stoneacre.co.uk/blog/egr-valve

In any case my first reaction would be to clean it.

https://pmmonline.co.uk/technical/ho...r-valves-work/

 

I agree with Meirion.
I am certainly no expert, but the EGR on our N/A cars is relatively easy to remove. Two cooling hoses and four bolts. Okay, two of them are PITA's; no room for sockets and only a minute turn available for an open spanner - But even I managed!
The EGR is a very simple device? it is just a valve whose degree of opening or closing is dictated by voltage and sensor wires connected to the ECU actuating solenoids. If it leaks air or vacuum, it can really only be the gasket? I removed mine, found that did not need cleaning, cursed and refitted it. As I mentioned before, if it is not functioning properly it is more likely to be an electrical fault? Wiring or failed solenoid? Like Meirion, I don't understand why you are not getting EGR Fault Codes?
Given my experience with this valve, I would conduct Pinpoint Tests before I even went near to removing it?

 

EsRay makes an observation of the way the E G R is removed, & it's connectors.
I do not see how another would need programmed to work, if a replacement was needed.

 

"I do not see how another would need programmed to work, if a replacement was needed."

A very good point

Time to find another Indy methinks.

 

Realized early that an honest, as well as competent, mechanic, was not an easy thing to find.
Affording ones time, was another issue entirely.
My answer was try to figure things out myself.
Reading manuals, asking questions, buying tools, with lots of bloody knuckles.
Neighbors all tell my wife, oh he can fix anything, don't understand his thinking.
They seem to hardly ever ask me, but ask her, to ask me about things.
Funny, but flattering at the same time, she thinks i intimidate them.
Have to admit it feels good helping your neighbor in need of a hand.
They never said a word about people on bikes, always in & out in the past summers.
Or my pit dogs, that were always inside their six foot, fenced yard, or my house.

 

I did put a factory dealer denso made in japan EGR on this car and watched the smoke test myself afterward. And the "learning" or calibration procedure I had mentioned earlier was nothing more than a reboot of the ECM it turns out. But I am still getting CEL with lean codes (only) and the smoke test is pointing only at the intake manifold interface to the head now. I started a separate thread for that.