Hi all. I'm new to the site, but have been monitoring for a little while. I just bought a 2000 Excursion Limited with 130k miles on the V10. It's main purpose will be to tow a boat, possibly a trailer, and for the wife to haul around 5 kids...
We test drove it before we bought it and everything was fine. Drove it a few hundred miles before taking it down to CA. It drove fine until we hit Northern CA. Check engine light came on, ABS light came on and Overdrive Off light flashed along with engine stalling... Quick google search pointed to the speed sensor. Fixed that on the way back north. Minor nusance until I got it fixed - hop under the Ex (plenty of room ) and jiggle the wires and it would work fine. After that, it was driven with no problems a few times.
Now comes the fun part...
Now after a while, it stalls and spews black smoke. In neutral, however, I can rev it slowly and it doesn't stall - just when I punch it in neutral or have it in gear. Service Engine Soon light is the only one that comes on now. I borrowed my brothers computer software based OBDII code reader to help diagnose. It would recognize that it was connected to a vehicle, but wouldn't synchronize. It connected fine to a Chevy and Dodge, but not the ford (yes, it is PWM compatible - my brother even bought the 'ford extended info pack'). I disconnected the battery to reset the computer. I hooked the battery back up and the SES light went off, but was still spewing black smoke. I took it for a spin in the yard (22 acres) and it ran fine. Took it down the road and the black smoke stopped. Brought it back and it hooked up to the code reader fine and reported no errors. Took it down the road again later and the black smoke and stalling came back...
I removed and cleaned the o2 sensor and noticed exposed wires on it. Taped them up when I reinstalled the o2 sensor. Now the code reader still connects when the SES light is on. Could that have been the problem with the code reader? The o2 sensor wires were shorting and screwing up the ECU?
It was still spewing black smoke and the SES light was still on after cleaning the o2 sensor. Unfortunately, I didn't think to reset the computer again, so I started looking at the TPS sensor. Unfortunately, I broke one of the tubes on the EGR valve sensor... I picked one up on lunch today and am going to install it tonight as well as reset the computer.
If it's still spewing black smoke and stalling, any other ideas on what to check next? I assume it's a sensor that requires the engine to warm up since it happens after a while of driving it. Unfortunately, it happened to me 20 miles from home in the middle of nowhere. I had to limp home by downshifting to 1st and giving it a little gas, then 2nd, then drive... Not fun getting stuck for over an hour with a 1 year old in the back seat in 90 degree weather...
Black smoke = rich fuel. Besides the o2, are there any other sensors that kick in when the engine warms up and help control the fuel mixture? There's no backfiring, but I assume that a rich fuel mixture can cause the stalling.
Lol. I'm a software programmer, but I sure hate computerized autos.

 

Maf sensor in the airbox. Seems that your having a problem once it goes into closed loop

 

Thanks. I'll check that out tonight and clean/replace as needed.
Btw, is that a '69?

 

02 sensors are also only used in closed loop.

Do u have and way to view data while its messin up. Scanner would have a live data button. U can get them at most auto stores. This would def help.

 

nothing's going right...
I installed the new egr valve sensor, cleaned the MAF sensor (no broken wires) and fired it up. At first, no check engine light. Then it came on and the black smoke came back. It's hooked up to the code reader, but it's reporting that my 2000 excursion is not OBD-II compliant and I can't pull any data - not even a list of the sensors...

 

R u sure it isnt a c.a.n system and not a obII system.

I would think bein a 2000 it would be obII though.hmmmm Im a gm mechanic so im not too familiar with the ford system. If u could get some data I could help with seein if anything is not right.

 

according to wikipedia, CAN wasnt approved for use until 2003. It has the correct pinouts on the odb port for PWM

 

Ok good to know, I thought a 2000 would be obII. Like I said im a gm tech haha.
But I can still tell u if somethin doesnt look right with the values if u could get'm. Hope I can help

 

I had some of the earlier problems that you described & swapped a bunch of sensors & small elec. parts. Still continued. Posted here & got good feed back, I spent a short hour removing & cleaning all the grounds that i could find on the block & body & put back together clean & tight. Spent some time on the battery cables too. No probelms since!! Worth looking at

 

A short is very possible. When I first turn the key on (engine off), it flickers sporadically before coming on. Relays are clicking sporadic in the power distribution box as well. Sometimes it seems as though it is in sync with the SES light flickering.
I disconnected the battery cable, waited 1/2 hour and reconnected and now the code reader isn't connecting at all again.
The ECU is under the parking break, but how do I remove it? Maybe there's a bad connection there? In the mean time, I'll start looking for grounds... Did you find many besides in the engine bay?

 

Almost 4am and I have it figured out. I went through and cleaned up all the grounds on the body and frame. Removed the ECU and found a Jet Performance chip that was not secured with the mounting tape. Cleaned up the contacts, put electrical tape to hold it and reinstalled the ECU. Fires up great, no SES light and the code reader connects just fine. Reads all the info, too...
Time to properly put the power distribution box back in and she's ready to go.
Thanks for the help everybody.
Anybody have any opinions about the Jet chips? Is it worth it to leave in? Or should I take it out. The boat I'm towing is about 3500 lbs loaded. Increased gas mileage would be ideal. I got about 13.5 on the fwy on the way to California and just under 10 on the way back towing the boat. Can I expect better without the chip? Or just leave it in?

 

If you can put the system back to stock you will be better off. It seems like your problems where caused by someone trying to modify things and they ended up screwing things up. This is why I want a used vehicle to be bone stock. I would pay more for one that has not been monkied with. One that has been modified with several thousand $$$ of junk on it is worth it's weight in scrap metal because you don't know what they screwed up in the process.

Perry

 

Once you hook anything to the hitch, expect 10 mpg. I have heard good things about the 5-star towing tune but others who have it would have to chime in on the mpg from it.

BTW you were amazingly positive in your posts as you were working through this issue, especially since the X is new to you and it crapped out so fast after you bought it. Nothing worse than plunking down a wad of cash to have it fizzle quick on you.

 

I ended up putting it back in after securing it with tape like the instruction manual from Jet says to do. I have a feeling that the guy I bought it from didn't now it was there because he didn't say anything about it. He only had it for 6 months before his wife lost the use of her legs and he lost his job and have to move. I normally wouldn't believe a story like that, but based on the state of his house (door frames cut for the wheel chair and stuff boxed up), it was very likely. It had new tires, breaks and wheel bearings. Got a good price on it, too. $6k I figured at that price, we could afford to replace a few things that went wrong. I just didn't think it would be this soon.

 

Lol. Wife just called... She was planning on taking it to costco. Good thing I told her to let it warm up for 20 min first.
Looks like I'll be working on it some more tonight...