Engine shudder

[ndiehm]

06 EB with 140k. Around 40 and 70 mph my engine shudders, this is under normal acceleration. If I give it more gas it shifts smooth. It's like the truck is trying to lurch forward. I know this has been discussed 1000 times but want to get ideas. I think it's one or more coil pack(s). Any ideas/thoughts?

 

[docraymund]

You could try checking the throttle position sensor to see if there are any flat spots.

 

[dmont]

I had the same exact problem and was concerned it was my transmission. In fact it was right around 160,000 miles. I ended up changing my coil packs, and it has run smooth ever since! Easy fix, and I purchased the set from Amazon. Good luck!

 

[gborree]

Highly likely coil pack. Had one go out 3 months ago and another one now. Going to just change them all out knowing that 2 will be a PITA.

 

[mike nadeau]

I just went thru a similar issue that went from 5 to 15 mph. Come to find out it was the range from 2nd to 3rd gear. It acted like coils but was actually one of the 1/4 check balls in the valve body. I rebuilt the valve body for around $120. Best decision I have made in a long while. Runs like new again.

 

[Aperez]

I had the same issue. It turn out to be a mechanical failure on one fuel injector (it was not closing properly so it overload the cylinder with fuel). I diagnosed the problem by removed all the injectors and testing them on the bench. Replaced the one failed injector (I could only afford one injector after I bought coils and plugs) and it's been running great ever since.

I followed the method from the video below to bench test my injectors.