I had to put a new EGR valve on my 95 4.9 recently and now the engine runs like crap. Its sluggish at low rpm's and it studders almost like its missing a cylinder. Someone told me that I should only buy a motorcraft but i didnt want to spend the extra $80. Does anyone have any ideas to fix the problem?

 

Check all your Gaskets sounds like you may have a vacuem leak

 

Providing that you don't have any block grounding problems or vacuum leakage problems, did you drive the truck around for a half hour or so, so that the computer could "re-learn" how to deal with a new EGR valve ????

Others may/will instruct you to disconnect the battery for 10 minutes or so to "re-set" the computer.


Bob

 

I don't think the valve itself requires a reset as the valve is vacuum operated. Not 100% sure on that, I just don't think it does.

I'm in agreement with MeanGreen460- be looking for a bad seal. Are you sure you didn't knock the tube loose @ the manifold when you were installing it? Or maybe break the vac line?

 

You're correct.....the valve itself doesn't require a re-set.

However, since FlaresideF150 stated "I had to put a new EGR valve on my 95 4.9 recently", one would have to assume that his truck was running with a non-functioning EGR valve.........hence his computer would have "learned" how to lean itself out (via the injector pulse rate) to compensate for for the "non-functioning" EGR valve.
Untill the computer has "enough time" to figure out how to compensate for the lean stumble he's experiencing, he'll get the infamous "EGR stumble" that 4.9's are known for.

Bob

 

Throwing this out there....
I went thru this a few years back and the "new" Egr was the culprit. Put a Motocraft Egr on, and no problems. That was on the 302, but a BWD Egr worked on the 300... Cannot explain but the difference I noticed was body and length on the 302 Egr.

Another note: Pull the Egr, and see if the spring inside the top, where Evp sensor sits, is not binding. Came across another problem that the spring was binding and not allowing the valve to seat, sucking in exhaust gases. If you push up from the bottom where the valve is, it shouldn't screech, bind, or catch.

 

Fair enough. I didn't consider that.