New EGR Valve Check-Could not get engine to choke

[V6Turbo]

Hi Folks,

Chasing high NOX and smog check is pointing at the EGR.

Verified the old and new EGR by pushing up on the diaphram and using Mity Vac. It will hold vacuum and I can get the valve to open up.

But when it is on the engine and hooking up a Mity Vac up, the response to the idle is very slight and not enough to stall the engine.

Is this normal?

Thx,

 

[RmvBfrFlght]

Can you reach up under the EGR valve and push the diaphragm up? If so then can also feel if the vacuum (mity vac) is opening the valve.

With the engine running manually push the EGR diaphragm up. The engine should stall immediately. If it doesn't then the EGR passages are clogged somewhere along the line. Which isn't unusual on a high mileage engine.

RemoveBeforeFlight

 

[ravege]

High NOx is kinda unusual on these cars, with low compression, etc. Do you have any way to verify if you are running lean? Having a 3-way cat should help, I know a lot of people toss the cat, or get a performance one, which will be 2-way (diff between 2-way and 3-way is that 3-way reduces NOx, 2-way doesn't). There's also the module which controls vacuum to the EGR valve - that could have crapped out.

 

[V6Turbo]

Can you reach up under the EGR valve and push the diaphragm up? If so then can also feel if the vacuum (mity vac) is opening the valve.

With the engine running manually push the EGR diaphragm up. The engine should stall immediately. If it doesn't then the EGR passages are clogged somewhere along the line. Which isn't unusual on a high mileage engine.

RemoveBeforeFlight

Yes...i pushed the diaphram up. Very Slight reduction in RPM but not stall. Same response with new EGR.

I also pulled the EGR off, cleaned with carb cleaner and verified functionality. It will hold vacuum and valve is responsive and not getting stuck. Diaphram is solid..no cracks.

Can a leaky gasket cause a no response on a good EGR?

 

[V6Turbo]

High NOx is kinda unusual on these cars, with low compression, etc. Do you have any way to verify if you are running lean? Having a 3-way cat should help, I know a lot of people toss the cat, or get a performance one, which will be 2-way (diff between 2-way and 3-way is that 3-way reduces NOx, 2-way doesn't). There's also the module which controls vacuum to the EGR valve - that could have crapped out.

I have a scanmaster. Not sure how to check if im running lean at idle.

Checked my fuel pressure. Im ar 42 to 43# vaccum line off.

Thx,