ok, so heres the deal... most of you know about my new LO5.. everything is just peachy with the performance, but.. i have a couple noises i dont really like that i dont really want around...

noise # 1 - car warm or cold, only when in gear, only @ precicely 800 rpm... if the car is lower than 800 rpm, no noise, and higher than 800 rpm, no noise.. it sounds like a REALLY BAD vibration.. i have a 1000w sound system and when my system is LOUD, i can hear the vibrations over that... i dont like it, sounds harmful..

noise # 2 - car warm or cold, only when accelerating... kind of sounds similar to the 1st sound, but mainly up in the 3000-5000 rpm range... when i hit the gas, the engine goes and very shortly after, the sound chimes in... sounds like vibrating, maybe grinding :-( i hope not...

noise # 3 - car warm or cold, only when in gear... sounds maybe liek exhaust leak, but i checked everything out and no leaks... almost a mix between lifters clicking (low oil sound..) and exhaust.. but both are perfect.. even after changing my oil, which i did just 3 days ago... the sound is still there...

any info at all would be awesome... i dont know if these are normal 3rdgen noises, or if they are LO5 specific.. i might have to find a caprice board for this.. :-( n e ways, thx in advance!

 

The first 2 could be a motor mount issue. If its a new engine, i doubt its a balancing act, though it could be. But if you really feel a shaking, id look into the motor mounts. Also, a peek at the trans. mount wouldnt hurt.

In what time frame did all of these start acting up? any specific order?

 

not really any order, just all showed up, and the mounts are ALL perfect.. i just replaced them all with the motor, both the crossmember motor mounts and the entire transmount and trans crossmember..., but, it wouldnt hurt to check them again.. dont know how they could have broken already... the motor has a little over 1k on it now, but the problems didnt get noticable until about 200, but still to this day problem 1 and 2 come and go.. but they havent gone in a few days, thats why im getting concerned.. problem 3 started as soon as i got home from the shop.. but it sounds like my grandpa's truck (1989 Sierra 2500 with a 350tbi in it) so i didnt think much of it

 

They may not be broken, perhaps loose? If the first 2 showed up at the same time, id suspect they are linked.

 

me 2... and they both happened right after i put in my custom chip and took it out for a drive... ill get under her tomorrow and give em a look... i wish i had my shop cleaned out... i hate not being able to work when its dark outside... but that third problem doesnt really get to me because it doesnt sound harmful... but its just the annoyance... i have a brand new engine and its already makin noises... i dont like it one bit...

 

If it makes you feel better i installed, well re-installed, a cam into a new engine, friend screwed up the lash and 11 of my 16 lifters are collapsed.

 

OUCH... give your friend a punch in the gut for me... I love workin on these cars though.. haha, come around september though, i will have started my UTI education... then ill be a moderator on here, hahaha.. cant wait.. but, back to the sounds.. now that i think of it, the sounds happening to me sound kind of similar to when i had my stock 305 in there... they did the same thing and my mounts were shot... deffinately checkin that out tomorrow

 

#1 sounds like the exhaust touching the frame somewhere.

 

its coming from the back of the engine, near where the distributor/flywheel, exhaust is... its probably exhaust, the distrib works all the time and the problem is only at 800rpm... so its not a bad distrib, and i just re-did the flywheel cuz i put in a new starter

 

your car shouldnt have a flywheel..

 

flexplate.. sry