[machine]

I've read through all the threads I could find, but can't seem to find a definitive answer.

Here's the deal, at ~1,400-1,600 rpms, if I start easing down on the go pedal to speed up without downshifting, the truck has a horrible shudder. It's kind of like when a gas burner is getting too much fuel, and not enough air. It's bad enough that it SHAKES the entire truck. I have to back out of it, and hit the go pedal enough to downshift. Anything over ~1,900 rpms is completely normal. Any ideas? Changed the fuel filters, and made no difference.

 

[bismic1]

Any codes?

 

[Smokin6-0]

You posted the RPM range, but did not say what gear. Is this in all gears or just in OD?

 

[machine]

Don't notice it much through the gears, but in OD it feels like it'll shake the truck apart. Only code I get is for a faulty ECU in my overhead computer.

 

[03F2506.0]

Check your injectors.... Mine did it bad in OD and I had to put a set of injectors in it.

 

[HerLifted350]

Mine did that right before it threw a code for an injector, if you were at a half throttle it felt like ya would shake apart, but when ya let off and put more into it, it would stop.... check all the connectors on your injectors when it's runnin... if you hit the right one, you will hear an audible pitch change... Just shut the truck off, and see if maybe it is just loose or you may need to replace it... Guys that worked on my truck just pulled the little U pin off, took it out, and put it back in... it had just worked its way out... Worth a shot, right...? Had me panicking that I would have to replace the injector, but someone here threw in checking that, and that's all it was. Good luck!!!

 

[Mpoage]

mine does the same thing. :doh:

 

[USMCpoolee]

Same here at 1500 rpm it shakes like hell

 

[Smokin6-0]

I am thinking you may have a problem with overdrive(transmission). Hopefully somebody with a little more knowledgle (Doug) will chime in.

 

[USMCpoolee]

if u find out what is wrogn with it let me know

 

[Mustangl3]

Mine does the same thing. I'm hoping its just the egr valve

 

[Fasttimez]

The shutter you feel is your injectors not getting enough oil pressure to operate properly due to clogging/coking ( commonly referred to as injector sticking)...the reason it's only present in OD is because the engine RPM has steadied out and between about 1,200 and 1,700 RPM in OD the load on the engine is so low that any heavy clogging in oil passages in injectors causes them to misfire or ( stick the spool valves ) by changing engine load you force more oil through the injector at a higher PSI....this problem is common on cold starts and gets better as the truck warms up due to the oil getting thinner and flows better when hot....if your truck is doing it all the time, hot or cold than an alternative to injector replacement is switching to a 5w40 oil and adding a product like REV-X....but remember these are not permanent fixes...there's no way to clean the injector properly without removing it....

 

[machine]

The shutter you feel is your injectors not getting enough oil pressure to operate properly due to clogging/coking ( commonly referred to as injector sticking)...the reason it's only present in OD is because the engine RPM has steadied out and between about 1,200 and 1,700 RPM in OD the load on the engine is so low that any heavy clogging in oil passages in injectors causes them to misfire or ( stick the spool valves ) by changing engine load you force more oil through the injector at a higher PSI....this problem is common on cold starts and gets better as the truck warms up due to the oil getting thinner and flows better when hot....if your truck is doing it all the time, hot or cold than an alternative to injector replacement is switching to a 5w40 oil and adding a product like REV-X....but remember these are not permanent fixes...there's no way to clean the injector properly without removing it....

That actually makes a lot of sense, as how the truck doesn't fire right up when I turn the key over, anymore. It cranks over a few times before it starts, and runs. So, basically, what you're saying, is I have to pull the injectors?

 

[Fasttimez]

The only way to fix this problem correctly is to either replace your injectors or pull them out, pull them apart, clean them and reassemble them ( But I wouldn't recommend pulling them apart unless you have experience at this ) Now a way to get some more life out of them is to switch to a 5w40 motor oil and add a lubricity additive like Rev-X or something...the thinner oil and the additive will counter act the deposit and coking buildup for awhile, but eventually you'll have to replace the injectors, but you can probably get about 50,000 miles of trouble free running, this will also give you some time to save for injectors....this was a poor design by Ford, the 7.3 injectors never had this problem despite being an oil operated injection system also...Ford scrapped this design starting with the 6.4....

 

[machine]

Guess I'll get some Rev-X, as I've been running 5w-40 synthetic for quite some time.

 

[Fasttimez]

Rev-X has worked miracles in alot of peoples vehicles...it's def. worth the price you pay, I should know cause I run it in my truck....it took care of my injector problem, but for how long...who knows...3,000 miles and counting so far with no problems...

 

[Mpoage]

Rev-X has worked miracles in alot of peoples vehicles...it's def. worth the price you pay, I should know cause I run it in my truck....it took care of my injector problem, but for how long...who knows...3,000 miles and counting so far with no problems...

Did it cure your shuddering problem or just calm it down some

 

[Fasttimez]

It totally cured my shuddering problem....but like I said, for how long is anybody's guess...I just added it this last oil change and after a couple minutes of running the problem was gone and hasn't come back...but i think the catch is you have to add this stuff to every oil change...which can add up pretty quick if you put alot of miles on your truck...I change my oil every 5,000 miles, I've put 3,000 on it since oil change + rev-X and no problems at all...

 

[USMCpoolee]

can you run rev x in automatics

 

[Fasttimez]

This is not for a Transmission concern....this is added to your engine oil to stop injector sticking issues....but according to Rev-X you cannot run this in an automatic transmission, only systems like Manual Transmissions, Differentials, Power steering, Transfer case and Engine.... Etc...