Question about 1999 Ford Expedition

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I have a 1999 Ford Expedition 4.6 and I have cleaned carbon out of the ports going to EGR valve and replaced the valve, but the car still bucks between 40 and 50 mph.????????????????????????

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  • jbandy Sep 29, 2009

    Could it be the EGR Sensor?



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You could have a bad valve or bad piston rings. Try doing a compression test. IF valve is bad you can do a valve job on it. If rings are bad you ahve to rebuild the motor. A compression gauge is about $30 or $150+ to have it professionally done. It is simple to do, takes about an hour

Posted on Sep 29, 2009


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Ford Escort P1405 Error Code

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

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Engine runs rough until it warms up

Lots of possibilities, from a vacuum leak to a bad coolant temp sensor. remove and clean carbon from EGR valve. and the port where EGR valve sits on engine.

Jan 20, 2012 | 1999 Ford Ranger SuperCab

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In my 1999 ford expedition 5.4 l engine i replaced the egr valve but thw check engine light came back after 4 days what could be causing this

Check code free at auto zone, If it is still telling you the EGR is the problem and you replaced it with a new unit not a used unit check your vacume lines for leeks.

Jul 03, 2011 | 1999 Ford Expedition

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Why do the hoses kep blowing off my egr sensor?

You have carbon built up inside the port on the intake manifold remove the valve and clean it out and the problem should stop

Nov 23, 2010 | 2003 Ford Expedition

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  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
  17. 9ecffd7.gif

Aug 10, 2010 | 1999 Ford Taurus

3 Answers

I have a 99 f150 that has a code showing its p0402 egr valve excessive flow the engine is a 5.4 how do i fix it

First make sure all lines are connected to EGR , if not ,connect them if they are? Then remove EGR value and clean and reconnect.

Jan 24, 2010 | 1999 Ford F150 Regular Cab

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Remove the throttle body housing on the top of the intake, it is a 90 degree tunnel like small piece held by 4 small bolts, turn it over and look for two holes, these holes are for the EGR valve flow, they are probably plugged up with carboned crud, clean them out with the tip of a screwdriver if neccessary to remove all the crud, once its clean reinstall it and reset your check engine light, hope this helps, let me know

Dec 04, 2009 | 2000 Ford Expedition

2 Answers

Anybody have step by step instructions on how to clean the egr valve on a 1998 ford expedition?

Well there is a plate the egr is attached to tha contain passages that build up carbon, most likely the egr is functional.Inspect and clean those passages first. As for the oxygen sensors there may be an underlying concern such as a Vacuum leak that contrbutes to the performance of the sensors, remember just because a code exists does not mean that a part is always at fault.

Jul 26, 2009 | 1999 Ford Expedition

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# 4 cyclinder

Number 4 cylinder is the 2nd cylinder back on the driver side. Check to see if your EGR valve is clogged with carbon. If it is, clean it out and I like to remove the EGR tube from the exhaust to valve and clean it out as well. The EGR tube is a metal tube. Remove the spark plug and see if it's been firing. How long has it been since it's had a set of plugs and wires?

Jun 29, 2008 | 1998 Ford Expedition

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