Strange vibrations

[IwantMKIII]

Alright, well, i've noticed over the past 5 days or so when my engine reaches op. temperature vibration begins to occur in the engine between 1500-3000RPM. I goes with the RPM and vibrates the entire car, no violently or anything just vibrate as if it were a gigantic cell phone on silent. It vibrates then stops breifly, vibrates through, stops breifly, vibrates through, stops breifly...and so on (almost as if the vibrations were when the ingition takes place, it goes through the cylanders 1-6 then stops breifly and starts over). Again this only happens a few minutes after it hits 182 degrees (water temp). Any ideas?

Also, my SAFCII is very untuned and running very rich 95% of the time. Timing has been perfected by my tuning shop but she still idles about 8-900RPM.

 

[BorHor]

OMG I just noticed my car doing this yesterday. Might be alignment but I dunno.

 

[LilMissMkIII]

Is it bad that i had a giggle at the thread title???

 

[BorHor]

Bad no but it gets annoying once you notice the vibration.

edit: yes it is bad that you giggled. GROW UP

 

[IwantMKIII]

Is it bad that i had a giggle at the thread title???

:rofl: lol, didn't really think about that

 

[87supradude]

Does it do it at idle or just when your cruizing? Why is your safc sooo rich? Need to upgrade injectors or raise FP?

 

[starscream5000]

Center carier bearing worn?

 

[ATL88Supra]

sounds like that center driveshaft support thingmine went bad and i replaced it with a 1 part shaft and it went away check the alinment too just in case

 

[87supradude]

That's why I was asking if he was moving. Have you gone over 40mph since it started? If that's the problem It should get worse with speed not rpm.

 

[F_T_F]

yes it is bad that you giggled. GROW UP

i dont wanna grow up im a toys r us kid

as for the problem, i had this same issue a earlier this summer turned out to be the bolts that tie the driveshaft and diff together needed some tightening

 

[IwantMKIII]

Remember, this engine is freshly rebuilt and gone through very carefully. The guy who built it races 7m's. It only happens when its to op temp. The vibration carries through 1500-3K in any gear at any speed. I runs extremely smooth the first 10 minutes of driving or so. I was thinking maybe more along the lines that the computer is trying to lean it so much its messing with the timing, causing bad ignition. It leans real bad at an idle only when its hot, otherwise it runs rich 95% of the time. Sometimes it leans so much at idle its off my A/F meter. Could that be a potential cuase....i just find it hard to believe it could be mechanical especially since its a $3500+ rebuild


i have 550's
lex afm
walbro 255
aero FPR
SafcII
and the list goes on...but those are more directly related to feul.

 

[BorHor]

as for the problem, i had this same issue a earlier this summer turned out to be the bolts that tie the driveshaft and diff together needed some tightening

Cool I'll look in to that thanks.

 

[F_T_F]

Remember, this engine is freshly rebuilt and gone through very carefully. The guy who built it races 7m's. It only happens when its to op temp. The vibration carries through 1500-3K in any gear at any speed. I runs extremely smooth the first 10 minutes of driving or so. I was thinking maybe more along the lines that the computer is trying to lean it so much its messing with the timing, causing bad ignition. It leans real bad at an idle only when its hot, otherwise it runs rich 95% of the time. Sometimes it leans so much at idle its off my A/F meter. Could that be a potential cuase....i just find it hard to believe it could be mechanical especially since its a $3500+ rebuild


i have 550's
lex afm
walbro 255
aero FPR
SafcII
and the list goes on...but those are more directly related to feul.

just for fun check your codes

and what are you using to monitor your AFR

 

[IwantMKIII]

I will after work, I'm just using an in car autometer guage