injector miss cause a shake?

[melmount]

This is it for me posting today. I dont want to ake up everyone elses time.
Can a failed or failing injector or two cause the truck to shake at certain speeds? For a while i could click off the od, rev the motor to stop the shake. Now that does not seem to effect it as much. But slow speeds its fine and highway. Its the inbetween thats terribel. Can it be caused by bad injector or injectors?

[melmount]

whats the three injector tests? buzz, contribution and whats the last?

[captivahach]

I know how u fell my truck is doing the same thing. I just started a thread yesterday, About my truck hopping kinda. Is the same thing that you have described in your previous post. I just installled new swamps inj. And its a no go on the cure(not the reason i installed the injectors). Also has a new convertor. Im thinking of trying the driveshaft balance also

[melmount]

I would think, in my case, that if its a u joint or driveshaft it would stay bad at higher speeds. Once over 45 i am fine. I was thinking converter. I caled brian at bts, he thinks injectors.

[captivahach]

mine does the same thing from 39 to 43ish it does it after that its smooth as can be only thats most the speed limit around here

[melmount]

Before you bought injectors did you have any tests done? did you just buy them anyway? I suppose it could be the icp,ipr? I replaced those. Its gotten better for me. I seem to drive around these back roads at 40, thats when mine shakes

[OneBigDoofus]

Originally Posted by melmount

I would think, in my case, that if its a u joint or driveshaft it would stay bad at higher speeds. Once over 45 i am fine. I was thinking converter. I caled brian at bts, he thinks injectors.

It vibrates at a rotating frequency and the faster you go the closer the frequency gets (finer), It prolly is still vibrating and you don't sense it.

[melmount]

How about this for an idea, I think it motor, a lot of you guys think driveline.
Theres a wire under the master cylinder in the harnesses. Its the grey harness. anyway, it locks up the tc via grounding from the computer. I in the past have spliced into this and hooked up a switch tolock the tc. I can remove tht wire so the trans can not lock the tc. Then the converter will work like old schooltc and always have a bit of slip. If i am correct the shaking at 40mph, which i feel is injector, gets a lot less noticeable, then its an engine issue or tc issue. If its the same, cause removing this wire wont change the tires, u joints balancing etc. then its not engine and it is a rotating something or other?
cool??
bob guzzle at Replacement O-rings for Ford Diesel Engines had a write up on the tc lock up mod. Thats where i got this.

[captivahach]

Originally Posted by melmount

Before you bought injectors did you have any tests done? did you just buy them anyway? I suppose it could be the icp,ipr? I replaced those. Its gotten better for me. I seem to drive around these back roads at 40, thats when mine shakes

I had a couple of test ran nothing major. Reason for the replacment was that my truck wouldn't start cold unless i had it plugged in. Since the new inj it starts really good now not had to plug it up since. Also, replaced the 8 gp inj harness, gaskets, ipr, and 8 inj.

[melmount]

I am thinking about unhooking the tc lock up wire. Where we are having these issues is real close to when the tc locks up. When tis locked the engine mishaps or misfires are much more noticeable. If i unhook and and its better to drive, then my issue is engine. If it changed nothing i need to check wheels etc.
I suppose you couldo it too. I want to know whether to screw with the wheels or driveshaft or the motor.