Strange problem that I cant figure out. My truck runs fine at idle and cruising down the road. around 50mph to 55mph I get this bump bump bump. Easiest way to explain it is its almost like its missing or something. But no Engine light is coming on. Its always right around that speed I can speed up past or drop down to it and it is always there. Trucks running great below and above those speeds.
I had a 100k tune up about 2k miles ago. Changed spark plugs and everything. Also replaced one of my Coils as it needed it but was assured that the rest were fine.
Please any help would be greatly appreciated. Thinking of taking it in and having them hook up something so I can go drive it and reporduce and hopefully catch something wrong before it gets real big.

 

My first guess would be a bad spot on your TPS (throttle position sensor).

 

You didn't mention the year or engine type for your truck. What you most likely have is a bad COP (assuming you have COP's).

Go to Autozone and buy a new one. Cost is about $50 bucks. Swap each COP one-by-one and take the truck for a drive after each swap. It's tedious, but you will eventially find the bad one.

My '01 4.6 did the same exact thing. Never threw a code. I took mine to the dealer. For $80 they told me which one it was. I then replaced it myself. It's your choice.

Good luck.

Anthony

 

Thanks Anthony,
Yeah that is what I was leaning towards was a COP.
However if U look at my signature it says I own a 2001 5.4L
Thanks for the help guess I will just bite the bullet and have them test it and tell me what is wrong with it.

 

Be sure to post the results back here for our benefit.