I have a 1992 Ford E-250 van with the 4.9L engine. I bought it about a year ago, and it ran pretty well for a while although the check engine light was on. A code reader indicated a problem with the EGR system. Then a few months back it began to start harder and harder and run very rough until the engine warmed up. The problem got worse every week, so I decided to replace a few things. I replaced the distributor cap, rotor, and coil (the plugs and wires were replaced soon after I bought the van), but the problem remained. I decided to replace the EGR valve, but when I started the van after putting the new valve there was a moderately loud bang, followed by a throaty roar from the engine near the manifold (I believe I have blown an exhaust manifold gasket, which looks like no fun to replace but I can do it). I let the engine run a bit, and it was idling very rough, basically like it had before, but after a few minutes the heat shielding that surrounds the pipe that goes from the EGR valve to the exhaust began to smoke, it was burning. I shut her down, then tried it again a little later, with the same results. Just in case I might have had the wrong EGR valve, I put the old one back in. Same thing- heat shield starts to smoke. So two questions: 1) given my admittedly brief description, does anybody agree with the diagnosis of a blown gasket; and 2) what would cause the pipe from the EGR valve to the exhaust to get hot enough to burn the heat shielding, and how do I fix it?

 

That pipe that goes to the EGR valve has broken. I had the very same thing happen and when I peeled away the heat wrap there was a neat little crack in it. Didn't take long for the little crack to turn into a big one! The tube at the dealer was $65, and the large nut that connects it to the manifold doesn't give easily. spray it well with PB Blaster and let it set for a bit then run the engine for a few secs to let the mani warm up. (with the air box removed and a steady hand you can get a wrench on it from the topside; if you can't you may need to remove the alternator)
You probably did in fact need the new egr valve. when they fail it is either burned out internally or frozen, usually open. installing a new valve that actually functions properly blew out a relatively thin metal pipe that had been made to pass an abnormal amount of hot exhaust gasses thru it and burned out. Not pleasant, but it happens!
Good luck with the job,
Tom

 

Thanks Tom! I will get under the hood again this coming weekend and check that out. I really appreciate the information and advice!

 

As much a headache as the job sounds like, tis much easier than the Mani gasket, lol...
Good luck!
Tom

 

Tom,
Actually I looked at it briefly last night; two weeks ago I had given this pipe a liberal spraying with Blaster; figuring it had to come out for the mani job anyway. So I put a wrench on it and amazingly it only took about 5 minutes to get the pipe out (with only one nicked up banged up knuckle, too!) and as you predicted there was a long skinny crack in the tube. It might be a couple weeks before I can get a replacement but as you say I am feeling pretty good about doing this versus the mani. Thanks again!

 

No problem at all my friend! That's what this site is all about!

 

not the smartest thing to do but it will work. take a crows foot socket and put it on an impact. watch out whten it breaks loose it will spin around like a fan blade but just give alittle tap the trigger on the impact and you will get the hang.
DO NOT HOLD THE TRIGGER JUST TAP IT GET IT A FEW BEATS AT A TIME !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

i appreciate the follow up solution. So many folks don't return to the forum to report how they finally fixed it.