EGR valve issues

[BIGTREAD]

Hey all. I've been chasing vac leaks. I have rough idle, flares, fades, stumbles in OD at low rpm. I tested the diaphragm by adding vac and it opens and closes properly. There are tiny holes on the underside of the disk rim. One in the back seems to pull air. Is this a leak, failure of this valve? Would this cause the idle issues?

 

[danwaters]

Have you scanned it. I had a similar problem and it ended up being my camshaft positioning sensor.

 

[BIGTREAD]

Dan, was your sensor bad? My mech just replaced the cam-shaft sensor. Not saying that might not still be a problem though.

 

[danwaters]

Well my sensor went out and it started having similar problems so I replaces the drive unit itself and that solver the problem. Mine just kept melting the sensors though. If yours isnt it may not be the case. The only EGR problem I have had was a gasket missing between the sensor and the unit. It wouldn't create vacuum but after a new gasket it fixed the problem. If you are getting sufficient vacuum pressure I dont see a problem. Have you ran the truck with the vacuum gauge attached. It should get around 5 psi while under normal driving/acceleration.

 

[BIGTREAD]

I suppose there could be a gasket issue at the EGR. Also my EGR tube coming up from down below wherever has a kink in it, and that too could be causing some trouble. I'm trying to figure out how to upload pics to this forum.

 

[SkyJumper]

If you are having a EGR vac issue, then you should be receiving CEL codes and should be able to to do a CEL read out and see what comes up. DO you even get any CEL at all. And if the EGR diaphram is ripped or leaking, then it should be recognized by the ECU, as it will try to compensate by changing the fuel / air mixture at spark.

 

[BIGTREAD]

Ford ran a diagonstic.
PO171, 174,303,305,306,340
In my quest for vac leaks I found only the brake booster fitting and corrected it. Sprayed a whole can of carb cleaner looking. And, the curious leak under the rim of the EGR valve. The suction test seems to indicate the diaphragm is working fine though.

 

[SkyJumper]

Question for you, do you have a exhaust leak on either side at the manifold? Because that is what PO171 and PO174 is pointing at.

PO303,PO305,PO306 are ECU picking up misfiring at number 3,5 and 6 cylinders. Have you checked the spark plugs and wires, and inspected each for chaffing or cracked wires and the condition of each spark plug?

And the PO340 is pointing to the cam positioning sensor.

 

[det107]

.....And the PO340 is pointing to the cam positioning sensor.

Can the code indicate a bad camshaft synchronizer or at least the bottom gear in off-position (not lined up)?

 

[BIGTREAD]

I have big doubts about the cpos sensor. Does anybody know if the engine will even run if the thing is a tooth out? Seems to me it wouldn't even start.

Plugs and wires. Absolutely was a major part of the problem. One of two mechanics I had work on this thing crossed two wires. I discovered it by pulling wires and discovering it didn't run worse! New wires and plugs now.

There is a kink in the tube coming up from the exhuast. I'm trying to get some pics uploaded, but still haven't learned how.

Also planning to use a vac and hose to do a quiet engine off leak test.

Thx for your input

 

[SkyJumper]

When you fixed the routing of the wires and installed them correctly, did you reset the ECU and run a bit and see what codes come up after? The tube you are referrring to, is it the EGR cross over tube?

 

[BIGTREAD]

I did not reset the computer. It immediately ran better, and...I suppose that is an important step. Won't the comp re-orient after 20-30 minutes of driving without being reset? (which I've done by disconnecting the bat for 30 min).

The tube looks to run from the exhaust to the EGR valve. It was kinked and straightend. Gotta learn how to get pics up on this site. The insert pic button only wants to see a web address.

 

[SkyJumper]

I The insert pic button only wants to see a web address.

You need to get a free membership to supermotors.org and load the pictures up from your computer to that website, then when you go to upload them, use the url from the location of your pic at that website to this. hen you will be able to see them here.

Go here to learn,
http://www.explorerforum.com/forums/showthread.php?t=147920

 

[SkyJumper]

My original question still remains though. Do you hear a exhaust leak from anywhere in your engine bay?

 

[BIGTREAD]

Skyjumper,

Okay. Did the vac leak test using a vacuum hose on the air intake. Found nothing. Unhooked bat for 30min, re-connected and started. Took 5 minutes of rocking and stumbling in idle to settle down. No eng codes showed up. Still found a vac leak where the EGR valve and EGR tube connect. Unbolted that. There is no gasket there...is there supposed to be, or is this a manifold type connection that requires torquing? And, other than that leak I hear no others including exhuast leaks.

(this youtube site suggests a gasket...http://www.youtube.com/watch?v=IqqhaQ92eYY) and that my mechanic has caused me a good deal of trouble.

I'll be about learning the pic thing now...
thx

 

[SkyJumper]

Did you reconnect the vacuum hose on top of the EGR after you were done?

 

[BIGTREAD]

Yes. The leak was definitely coming from the joint between the EGR and the EGR tube. What do you think of the kink in the tube coming up from the exhaust? My mechanic said it wouldn't make any difference, but he's the one who assembled the EGR with no gasket!

 

[SkyJumper]

Yes there is a gasket there. If the gaasket is missing, or part of it is gone or is leaking then yes it will require you to replace it. Have you ever had the EGR off before? The gasket should be there unless it was put back together without it.

 

[SkyJumper]

Also, I just checked and you have 2 seperate threads going on this same issue, except that you never stated that you did a swap of the engine from a 00 to a 98 engine. As mentioned before in the other thread, the setup on the fuel regulations is different on both yrs. If the ECU for the 2000 is still in your truck and not the 98 ECU, then your issues are propably from that, and the ECU is telling the engine all kinds of crazy **** vs it being able to read the engine correctly if the ECU was the 98.

Where is the ECU that was from the 98? And why did you not use it, and anything else that would of came from it? Wiring harness, fuel delivery and maintenance and what not.

I was made to beleive that this was a stock issue you were having, with 2 threads going at the same time, defeats what you are trying to solve. You need to stick with 1 thread as we all can see what the hell is going on from start to finish.

 

[BIGTREAD]

skyjumper,
Yes this is true. We covered the fuel rail issue. Checked at 65psi constant. 2000 rail with 2000 cpu. Mech said everything topside came off the 2000. I started the EGR thread because there were nobody but me talking on the swap thread. Meanwhile the crossed plug wires corrected straightend something out, and EGR w/no gasket are looking like major culprits. I still don't know if the camposenser is right, but no one seems to know what the eng will do if the sync is a tooth off forward or backward. After I reconnect the EGRv w/gasket, I'll drive it to see what codes if any it throws. I figured I'd clean all this up in a clean problem diagnosed thread for the record when the problems were solved. After reading so many threads on idle and stumbling in OD I got the feeling the problem was of a more common origin, vac leaks, wires, bad sensors. Been following everyone elses path here. There were a couple of weeks where this explorer ran great after the swap so something must have been right at one point.