Hello everyone. New member that needs help. Long story so bear with me . I'm located in north alabama and you guys have awesome help topics that is desperately needed. 2001 7.3 Ford excursion 4x4 limited. I have a shudder , vibration,or miss fire that I have been chasing for a year and half. Tranny, torque converter, driveshaft ,8 new injectors still no luck. Been to 3 shops and every diesel shop says the same thing. Can't figure it out. In neutral it will vibrate,shudder,or miss from about 1100 rpms on. Driving down the road it's really bad between 4th and overdrive. Flex plate is 20/1000ths and I believe spec is 50. If it will do this in neutral doesn't that rule driveline out? The last shop ( very knowledgeable) said they had no clue what was causing it. The truck is bone stock. No codes no check engine light nothing. Had a couple of codes before injectors went in p0603 and p0605. But I think that was from the new batteries I put in. Cleared codes and they haven't came back. IDM ICP CPS EBPV ALL WERE checked. Could it be a faulty ECM? Belt has been removed to rule out pully accessories alternator, power steering pump etc.Have 55 psi fuel pressure # 8 on the compression was 390 and the other seven were between 410 and 420 I think. Truck starts fine idles fine and runs great except for this annoying problem. Tires are perfect new leaf springs billstein shocks new rotors calipers pads . The same feeling in neutral is the same feeling while driving. At a loss , I meticulously maintained it since I have had it. I look forward to figuring this problem out because I know the people on here have more knowledge than me. Thanks in advance.

 

Motor mount?

 

Thanks nicmike. Checked those first. This feels just like a out of balance driveshaft but it does it sitting dead still and light throttle. Starts about 1100 rpms on. Keep the suggestions coming.

 

Weird issue. I've got the same year as you. Have you changed your Throttle position sensor?

I just replaced mine because it had an off idle dead spot and it would oscillate between some Rpm's. It's a cheap easy change. 10 minute. I put a Dorman on mine. It was cheap and it worked, for how long we'll see but it's good for know. Part# 699-200

My excursion is Early year model. Have you dropped your fuel tank lately? Might be picking up crap off the bottom > Idk. Just loading the shotgun here.

 

I actually thought about dropping the tank, but have 55lbs of fuel pressure. TPS might be a good start because it's cheap. It's weird what it feels like. It feels like the motor is moving/vibrating. Motor mounts are good. Starts at 1100 rpms. It's very noticeable in park and open road driving. Could it be a faulty IDM without throwing a code. Thanks in advance

 

Also it does it with the cruise on as well.

 

Check out Bill.

Cracks me Up! Funny.

Do you have a tuner with gauges can you watch your ICP or any other parameters while driving>

 

Thanks. I know it's not a cracked block. My excursion is bone stock and the guy who bought it new is 82 now. It's never been touched. I am known as paw paw the way I drive. Since I have owned it she has been babied. Keep the suggestions coming tho

 

Forgot to mention 170k on the odometer

 

What does your balancer look like?

 

Balancer looks great. I'm telling y'all this is a ghost I'm looking for.

 

And for what it's worth it does is when the truck is cold and at operating temp

 

Check the wire harness that lays on the dr side valve cover. Could be shorting an injector at a certain voltage (above 1100 rpm).

Check or replace the valve cover gaskets as they transfer electrical to injectors.

Have you checked your fuel bowl for water or leaks? Is the fuel supply line leaking at the bracket? Could be sucking air. Have you poured in some diesel 911?

Is the PCV clear? Pull the intake tube off and look at the turbo inlet, excessive oil?

The only other thing I may suggest to rule out air in the oil or fuel systems, put the oil cross over tube on the heads and put a fuel bypass system on it. It helps a great deal overall and will also negate the possibility of trapped air in the systems.

I had my diesel guy hook up his Fluke and we drove around for an hour looking at everything under all driving conditions. He checked every aspect of every system. Hopefully you have a shop that can do that.

 

Thanks carbon coupe. I will look into it. This thing is a ghost.

 

IPR? Be sure to check the harnesses near the connectors for ICP and IPR especially.

Might want to jump over to the diesel forum, which can get you some diesel-specific help: https://www.ford-trucks.com/forums/forum31/