Hi guys its been a while since i posted on here but ive still been browsing alot. i finally got my 1994 camazo z28 to work in 100% condition for about.... 2 days ...... and what else is new..... another problem. i just finished the rebuild back in july and threw in a new performabuilt transmission in august.... and ive been having spark plug wire issues cause of the headers but i finally got that straightened out with some shielding on the wires. so thats the background of whats been wrong with it since the rebuild.

i was on the highway the other day like i always am in cruis control at like 70 ish and knowticed the car was acting a little strange...... and when i took it out of cruis control it was acting very strange... when i gave it gas it wasnt accelerating like normal and the pedal was vibrating alot. so i got it home and looked to see the alternator bracket broke off but the alternator was in place... we had built a custom alternator bracket to put a smaller alternator and normal 350 valve covers on it. that was no big deal so i fixed that.....

but when i started it up it was knocking.... not loud... not on top of the engine but fron under the car you could hear it. it was knowticable and the inside of the car would kinda thump every time it makes a knocking sound. just today i started it up in cold weather too see what it would do because it wasnt knocking until it heated up.

every time i brought the rpm's up to about 2k it would sit there perfectly fine for about a sec then at an intervan of about a second it would dip down 2-300 rpm then come back up.... i have no idea what it up with this thing the new engine only has a little over 2k miles on it and i broke it in properly and have done many oil changes and everything. and im not racing this car or driving it hard at all....

theres no explanation i think it might be a flex plate bolt that came a little loose or something and is rubbing under the car.... but that wouldnt cause the rpms to dip....

any help is appreciated... thank you for your time and for reading my short novel.

and for those who are curious heres the car back when it was healthy but before i put on the cold air intake and a list of mods.
http://www.youtube.com/watch?v=k37kmj2GW6Q

 

no1 got any aideas at all?

that cant be good lol

 

Pull the dipstick and check for metal first... doesn't sound too far off from a bearing. A rod knock can feel like a hammer on the floor board.

If a bolt was rubbing on the flex plate / flywheel it could for sure cause the rpms to dip... but so could the bearing.

Did the belt stay on when the bracket broke? Did it get hot? I see electric pump is a work in progress.

Check oil for water and the water for oil in it - Everytime I have blown a headgasket it runs like poo at low rpms and shakes etc.

Any codes or lights on? All the wires good now? A missfire can be violent from a bad plug/wire.

Just some ideas

 

ok sorr for not specifying tose i should have known better.

no metal/water/gas or anything in the oil. the oil pressure is same as always and i have very high quality amsoil synthetic in the engine right now so i have a hard time beliving one of my bearings has goner seeing as it is a 4 bolt main.

the water pump thing was solved back like a month and a half ago but the car did overheat one time when there was only like 200 miles on the engine... i wasnt driving it it was just idling and i went to pull out of my friends driveway and it started running like **** and started thumping and i turned it off but the engine has been fine for the past 200 miles so i dont think it did any damage.

i have had many plug wires go bad and the thing has misfired alot... i mean alot.... but i finally got that all fixed up it took alot of experimenting to protect the wires from the headers.

i sure as hell dont think i blew a head gasket because they are brand new and i havent pushed the engine hard or anything.

o and the belt and everything stayed on when the bracket broke the alternator just shifter a little bit.. no biggie.

i dont see how the bolt could make the rpms dip like that... the car feels like its stalling for a sec and revs back up.... not like its stressed or has some force against it.....