Heres the prob: 2002 5.3liter with 94,000 miles on it, starts fine-engine is noisy due to lack of oil lubrication on initial start up. but mine is a little extra noisy. seems to idle fine, sometimes lopes a little bit. when i give it little gas and hold it(about 800-900rpms) the engine shakes like crazy-vibrates the whole body. above 1000rpms shaking goes away. ive heard about cam lobes getting worn, but i am not sure that this is the problem. this engine has had much abuse (a lot of high rpms), but always the finest maintainance(Mobile 1 full synthetic every 3000 miles religiously, fuel filter every oil change, new plugs and wires,etc).
Any help will be extremely appreciated. I would love to continue going to the track, but i do not know if i am just doing further damage to an exsisting problem.

 

bump ttt

 

anybody?

 

Have you cleaned the t-body and IAC...maybe TPS going bad? You could get it scanned,too.

 

It's a roller cam so i doubt the lobes are worn. How do you have low oil pressure tho? A tic at start up isn't usually low oil, its just piston slap until they get to operating temp.
Does it sound like it's missing when you hold the rpm's?

Just a few questions that may help your process in finding the answer.

 

no, you're right i dont have low oil pressure- always excellent oil pressure
but when i hold it just at around those rpms, it feels like the motor comes out of balance..kinda like how a tire and rim will can vibrate at a certain mph, then become smooth at a higher speed. i wish i was a mechanic, cause this has me baffled, Haynes manual says it could be like 4-5 different things.
Also, thanks for the help guys

 

not sure i can get it scanned if im using hp tuners....

 

Yea, u can its no different than stock for scanning.

Also, there is no ses light? is this all the time or once and a while, how long has it done it? could it be bad gas? or bad wire? bad plug? ect?

 

its done it for a while now and maybe getting worse, no ses at all, maybe my tuner turned it off, but all your suggestions, except for bad gas make sense i guess.

 

Does it do it in drive...for example you're at a stop sign at about 550 rpm and as you accelerate through 800-900 does it stumble or shake?