Service engine light is on, I've replaced the egr valve and the solanoid, what is the cure for this lite?? how would i clesn a clogged egr valve tube and passage.

TYPE: OBD PO401 & study the code

I think your best to have a professional use
the proper testing tools, to actually find a problem

You can throw parts at it for a long time, if you do not
understand the system your working on, or have no factory
service manuals or trouble charts to follow

I see you said you got a part replaced

So the shop failed to road test or look at data to confirm
the repair,too bad,that seems to be the problem the last 25 years

Here is a list of possible causes. Some things you have already done.

EGR solenoid valve harness is open or shorted
- EGR solenoid valve circuit poor electrical connection
- EGR volume control valve stuck closed
- Faulty EGR Pressure sensor
- Faulty EGR temperature sensor and circuit
- Faulty EGR Valve
- EGR passage clogged
- Exhaust gas leaks
Read more: http://engine-codes.com/p0401_ford.html#ixzz28fATCih2

Follow the link for help with this fault code P1405 Ford DPF EGR Sensor Circuit High Voltage Detected

I suggest you replace the EGR valve position sensor.

Are you sure you have EGR flow?? Hold the EGR valve open the engine should run poorly, if not you have no flow.

Could be a clog in the tube going to the EGR valve, or in the tube/hose leading away from it!

When you cleaned the throttle, did you also clean out the pathway for the egr valve. I have seen these get completely clogged up. And if they are partially clogged they can pop a code. This also goes for the tube that comes from the exhaust.

The EGR Valve and System - it's just three letters, but EGR can result in AGGravation.

Common in automobile emission systems since the early 1970s, the EGR (Exhaust Gas Recirculation) valve controls an engine's emission of smog-causing nitrous oxides, or NOx. Its job is to route a portion of the exhaust gases back into the intake manifold. That lowers combustion temperature to below 2,500 degrees Fahrenheit - the temperature at which NOx gases form.

EGR flow is controlled by the engine's computer, which opens or closes the valve as needed. The EGR system is, for the most part, in the "out of sight, out of mind" category, and typical doesn't require regular maintenance. But if it gets clogged with carbon deposits, you'll see your "check engine" light come on, and a code (perhaps P0401 or P0402 or P0403) will show that there is insufficient flow. That typically results from a vehicle being driven persistently on short trips that don't allow the engine to fully warm up. Flow problems also can be caused by carbon buildup due to failure to change the oil frequently enough.

A clogged EGR valve not only results in higher emissions, it can affect fuel economy and cause rough idling - even serious engine damage. Valves can usually be cleaned, but replacement is often recommended.

A code P0401 most likely means one or more of the following has happened:
* The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (tube), most likely carbon buildup
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum

Possible Solutions: In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit.
* Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's & DPFE voltage. There should be a noticable difference in RPM's with the EGR open
* Clean out the EGR valve and/or tubing to remove deposits
* Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model)
* Replace the DPFE sensor (with a good quality / OEM one)
* Replace the EGR valve

1. po401 refers to an insuffient flow of EGR gasses
2. locate egr valve
3. with engine running at idle
4. on the underside of the valve you can access the diaphram.
5. wearing glove if ness
6. lift diaphram while idling
7. does engine stall or run very rough?
8. if not remove valve
9. start engine
10. you should hear a very large vaccum leak and exhaust noise
11. if either are missing investigate cause
12. if ok reassemble.
13. locate DPFE sensor
14. inspect sensor for damage
15. inspect hose to sensor for damage
16. replace sensor

It may be, but the code will specify what the problem is as a lot of things can trigger an EGR code. There are numerous codes that relate to the EGR, but the individual code will usually pinpoint what the issue is.
Some causes could be the DPFE sensor is faulty; there is a blockage in the EGR (tube), most likely carbon buildup; the EGR valve is faulty; the EGR valve may not be opening due to a lack of vaccuum

if it is for the EGR valve again, replace the valve and the DPFE sensor. Not sure what an EGR regulator is. Could be a bad hose going to the DPFE, or a clogged tube or EGR port also.