Yesterday my van began "stumbling" when started...meaning after it cranks, it'll stumble...kinda misfire for a few seconds then usually return to normal idle. Sometimes it'll stall instead. It seems to only do this after sitting for more than 20 minutes...if I shut it down, and immediately restart, it fires up just fine.

I had some "work" done on my van earlier this year. You can see everything in THIS thread, and photos are in my gallery.

When I got the van back, it seemed ALOT less powerful, and got miserable fuel mileage. Now, I expected decreases in both with the weight that was added, but I calculated 12-13mpg highway during drives to north jersey. I think that is exessive.

At the same time, I noticed that when I work the van hard, "get on it" so to speak, it stinks like rotten eggs...if the windows are down, its damn near unbearable. My brother driving behind me could smell it. During normal driving, the sulfer smell doesnt seem to show up. I'm thinking a cat or two...or three may be shot.

Its got 34k miles, so its under warranty technically. I'm kinda worried about a dealership giving me crap about all of the modifications...not to mention the increased difficulty of doing anything to the van. The doghouse cover removal is a job in itself. Its surrounded by computers, wires, brackets...it even has a wire running through it with a switch mounted to the front.

A tech cant drive it, either. My ignition and transmission are controlled through a touchpad. I suppose I could put the seat in, and teach someone how to operate it, but then again I cant drop it off overnight since its my only accessible vehicle...I'd be stuck there.

I plan on calling a dealership monday...I'm just kinda wondering if its gonna be more trouble than fixing it myself. Any of you guys working at a southwest NJ Ford dealer that can help me out?

 

The cat definitely sounds like the problem. Does it get mostly short runs? Sometimes that can plug the cat. All your problems could be from a plug. If you let it go and it continues to get worse, then the cat is plugging up. Eventually it should spit out a code and you'll get a check-engine light.

As for the mpg, I get 15.5 on my 2000 E-150 with the 5.4 at highway speeds going 70-75 mph.

 

When it stalls out in the beginning,if you can activate the throttle will it stay running?
If so I'd also look at the IAC valve.this controls the idle air into the engine.
they rotten egg smell may be because it is going to closed loop runing rich because a few things
dpfe sensor clogged
egr valve not working or stuck
o2 sensors
they need to scan the vehicle at the dealer get the codes.
Rich

 

Does a 5.4 throw codes without a CEL? I wondered that the other day when, for the 2nd time, mine died when I started it with the remote start. It had always stayed running before. I checked for codes but there wasn't any.

 

When I change my oil in my 4.6L's or my V10, I pull the fuel pump fuse and crank until I get pressure.

This is sure to log a code, but does NOT light the CEL/SES light. The code is there if I look with Autotap.

I took it from that thread you are wheel-chair bound? Any of the mods you do to it are for a disability - it would be very hard for Ford to not warranty your van. As long as you can prove that nothing you did would affect the actual engine (throttle cable is not an electrical connection), they are stuck trying to deal with it.

The rotten egg smell is the cats dealing with a rich condition. Could be that someone disconnected the O2 sensors during the work and never put the connectors back? DId they work on the exhaust? Usually I see a lot of lean conditions with the modulars on this site, but rich, stuck injector even? Check the plug color and see if one cylinder is running real rich. Of course, have fun getting to them in that van ...