Hi guys I have a 2001 econoline van with a 4.6 motor. It has a little over a 100,000 on her. A few months back it started surging or chugging when I would be driving about 45mph. so I took to the dealership and they changed the fuel fiter,spark plugs replaced one coil and just did a tune up on it got back it did again. Then it went away for about 2 months. It came back again and this time the check engine light came on it said it was the egr valve. So I took it to a real good mechanic that I know he changed it. It ran good for a day then it came back. with the same engine code for egr valve. So I took back the mechanic I know He can not figure it out. He said all the coil packs look good and the spark plugs look good he checked all the vacum lines he said they were all fine. Its getting frustrating because the computer keeps saying egr valve and we replaced it. So I am wondering if any one elese has had this problem and If so What do you think the chugging problem is. Any help would be appriciated thank you.

 

Welcome to the forum.

You could have clogged EGR ports in the intake. This can happen over time.
You could have a bad EGR sensor. What is the exact code that you are getting?

 

I'm going to go out on a limb and say that there are two coincidental problems:

1. Lxman's diagnosis is correct about the clogged EGR ports.
2. The chugging at 45 mph is Torque converter shudder - change trans fluid

 

Ok i will look into that And see what I come up with thanks for the suggestions.

 

I had a similar situation and found that the vacuum tank under the right fender was leaking and did not have sufficient volumn to keep the egr valve open.

 

1998 F-150 4.6L 4x4 - 142,000 miles

Same problem here, also.

A small "surge" with the RPMs at ~1,600 and going about 45mph.

Figured on it being a fuel injector, but it looks like it's something else.

What are the chances on it being the torque converter?

Nightrain

 

They usually shudder when locking up, but then quit. How old are the plugs/wires?