OSS = Output Speed Sensor - located on top rear of trans.

More info here:
https://www.ford-trucks.com/forums/7...ml#post6161468

Ed

 

Got it...thanks!

 

Update for tonight.

Got home and replaced the OSS. Plugged in the laptop and did a scan - it still showed the code from yesterday so i cleared it out. Fired up the truck and was going to go for a little test drive - as i backed out of the garage it died on me and got my P0720/0722 codes again

While driving i had the scanner running and at one point i thought i saw the input speed sensor on the transmission jump down to a zero instead of registering a RPM - this happened a couple times. Sad part is I thought i had the scanner recording the session but i guess not so i can't review it.

Along the same lines as that - while i was driving i had the scanner monitor the OSS and TSS. Both of those were registering numbers while driving and i don't think they ever dropped to a zero number - unless i was stopped of course.

The scanner only showed one misfire the druation of me driving around - but i sure felt the rough running a few times. I was probably out for 5 miles or so and from 25-55 mph roads. One section has slight uphill to it so i tried to ride it around the 1250 rpm range again and i was able to get it to 'shudder' or 'run rough' - whatever this problem is to happen again. I glanced over to the scanner and it wasn't showing any misfires during this part either.....

Kind of has me wondering about that input speed sensor on the transmission now. Ideas?

Ed

 

With this many different things happening consistently, it has me wondering about the condition of your grounds. I've seen more than one car that wouldn't run right, no matter what was done fixed when a bad ground was found and repaired.

It may be worth your time and money to buy access to Ford's shop manual. I was looking on their site the other night and you can buy 72 hour access online for less than ten bucks and a month for about ten bucks. That includes the whole shop manual, transmission, TSB, everything. Might give you some leads, and it includes all the wiring diagrams so you could find and check your grounds.

 

Update from yesterday - not a good one.

The sensor i had was a loaner 'good' one that i put in. Figured was worth a shot since it is real easy to get to and only takes a couple miniutes. Last night i had to stop and pick up a part for another vehicle (for just in case) and as i was trying to back and pull out of the little parking lot the truck died 6 times on me. Then when trying to pull out on the main street it did it half way out. Got it going and a block later is a stop light - did it there as well...

So i'm thinking things are worse so i put my original sensor back in and start poking around and looking at wires and ground connections. Nothing seems bad. I fire it up and truck idles and runs fine just sitting there. Went to back out of garage and it was fine - pull out of driveway and it dies one time.

I take the truck out for about 5 miles - make couple stops - all good. Pull into a parking lot and do lots of reverse and forward starts and stops - still all good.

Take it home and call it a night - i'm outta ideas for now. The one thing that i'm still wondering on is the Transmission Input Speed sensor cutting out on me the one time while i had the scanner on it.

So today i'm driving my wheelin rig to work so i can have a break from the truck and what does it do? Tosses the power steering belt on me - all i can do is laugh

Ed

 

Well just for the heck of it i picked up a new TSS and put that in. Was doing this only because of what I saw that one time when I had the scanner hooked up and saw that it went to a Zero reading while driving.

After the quick install - this one is even easier than the OSS I fired up and went on a test drive. Went about 10 miles on highway and back roads. Pulled into a parking lot and did a couple backups - added some brake just to simulate a little load.

With all this the truck didn't run rough even one time or die on me. I'm not getting my hopes up just yet and i'll take it to work tomorrow to see what happens.

Ed

 

Well after the test drive last night and going to work, running around at lunch doing some errands and then heading home it finally died on me. Happened twice at stoplights on the way home. Sitting there at red light - foot on brake and all of a sudden it starts running rough and dies on me.

When this happened the truck was stopped and I was just waiting on the light. When i got it running and left it in Park it ran just fine. Guess i'm back at tearing into it starting tomorrow....

I still have not found any wires that may be giving me problems. I sure was hopful it was just a sensor

Ed

 

Hope you find it soon. Good luck. I'm waiting to hear what you try next and what the result is.

 

I'll have another vehicle to drive starting tomorrow so when that happens i'll be able to dive in a bit more and not have to worry about what i'm going to drive the next day.

I was reading somewhere that someone had an issue 'sort of' like this and it ended up being something with the alternator. Even though it tested good they had it rebuilt and that helped..... Just another thought but rebuilding has to be better than buying a new one. I'm also trying to find somewhere i can have test the computer as well but i've not had much luck searching on that solution yet.

I'm working on what i read here and things to look at. I've been going through my shop manual also.

So far what i've done.

When i thought it was a motor running rough issue:
Cleaned MAS
Cleaned the K&N
Checked plug boots and looked for water
Pulled plugs and checked them
Replaced fuel filter

After figuring out it wasn't a motor issue:
Replaced VSS
Looked for bad wires
Replaced a battery that was in since June 2003
Replaced end on negative cable and checked other ends
Checked wires along rear of driver side head that goes down for bad wires
Checked wires from VSS and OSS a ways but not all the way yet

Did not see any metal residue on the VSS or OSS when i pulled out but i probably should change the trans fluid while i'm at it.

Thats where i'm at for now,
Ed

 

Took a break from this for a bit but was messing with it tonight. Got the trans fluid and filter changed. Couldn't even back out of the garage without the truck shutting off. Even got the check engine light to come on this time

So i went back in the house and grabbed the laptop and hooked it up and ran a KOER test from the scanner software. The one thing that catches my eye here is a reading on Cylinder 1 - shows a value for a misfire? I'll try to get the image posted and see if anyone has an idea or what....

Also showed a P0703 and P1780 code after running the KOER test...... fun times. UPDATE: Found info on the KOER test - guess i didn't hit the button, turn the steering wheel, or step on the brake. Will give it a whirl tomorrow and see if those codes don't show up again.

Thanks,
Ed

(might be little small so click here for original located at Picasa - you can zoom in there)

 

So had some time this weekend and went and dove in on the truck again. Based on the KOER test from before i cleared the info and ran it again to see if i came up with the same results.

Ran the test and the same misfire error that showed before came up again. So i cleared it and installed a new coil on cylinder 1. Crossed my fingers and ran the KOER test again - this time no misfire error.

Been driving for two days and 'so far' its being nice. Lots of errand drives in town with lots of stop and goes. I have not had it stall out on my yet - though no that i've made it public it'll probably crap out on me

Will give it a couple more drives later this week - we'll see....

Ed

 

I have just been through this check your crank shaft sensor.

 

NitroRC:

Hope you can give us an update. Was Cyl#1 COP your issue? Have you had any other issues come up with the same problem?

Does anyone else have suggestions on how to use AE to diagnose COPs and plugs and/or analyze misfires?

 

Truck has been running great after the COP replace

That is until Saturday July 9th and she filanlly blew a f'ing plug.... But ill start a new thread for this issue.

Ed

 

Stumped????.....I have a 2000 Excursion V-10 Limited with 115k on it.....I bought the vehicle in January of 2012.....Before going on first big trip with it I had the oil changed to synthetic, and had the local Ford dealer put a brand new fuel pump, and 10 brand new OEM coils and plugs......The last 3 rain storms truck has been running very rough with gray smoke, smells like burning raw fuel then changes to black smoke the more I accelerate the RPM'S it starts to clear up a little but runs really rough.....And better yet, there's no check engine......Any help here would be greatly appreciated.