Car has a really bad scream/high pitched whine....and has trouble idling, it will drop low, jump back up, drop low again(I think IAC maybe?). Also it smokes a little bit, coming from pass side under exhaust or the back near the dizzy I think...And I am not very confident that the coolant is flowing into it, and pretty sure my temp gauge isn't working as well(might be because no coolant is reaching it as well?) so it makes it really hard to tell and worrying...any particular way to check if coolant is going through the engine or not? Like it seems like the tstat isn't opening or something, but yet it had enough pressure to shoot coolant when it had a leak, was squirting out of the LIM pipe fitting, fixed it and checked the coolant. I'm thinking about removing the tstat to see what happens but that will run it a bit too cold.

 

Did you replace the water pump when you dropped the 3.4 in? Let's just say I learned that the hard way... Six weeks after the 3.1 was put in my car, the water pump failed and cost me $250 to have replaced. Made some nice screeching noises before it failed .

Other than that, is everything tight? Did you replace the belt and clean the pullies with a degreaser to get the coolant off? Is the belt tight (within the scale on the tensioner)? Is the tensioner pulley new or used?

 

we might be in the same boat with the screaming..when my car hits 2k-2.7k(ish) rpms it has an incredible high pitched noise that echoes inside of my car. it only started happening after i got exhuast on it, its a stock 2.8l. they replaced the muffler with what they called "fake flowmasters" i didnt bother questioning them because it sounds great except for the high pitched buzzing. but it could be completely different for you.

 

reused WP, pulley and tensioner are brand new though, when it screeched was it constant? thinking ill pull the belt and see if it stops...also thinking about pulling the tstat so I can be dead sure theres coolant in the engine. I know these engines don't like running that cold...but better cold than hot. Is there really any way to test if coolant is getting past the thermostat? I have reservations about driving it and not being sure its getting coolant, think I need to do an idle relearn too..And while the noise could be exhaust, I rather doubt it...just doesn't sound like it could be.

 

take the belt off and start it up see if the noise goes away, if it does put the belt back on and get a big screwdriver.start the motor and place the flat part of the screwdriver on the altanator and put ur ear to the handle. do this to each accesory u will know when u find the one thats making the noise

im wlling to bet its the altanator.

btw if the motor still makes the noise with the belt off im going to bet on a spun bearing.my friend had an old duster with a 340 and 4 speed one day it started squeling and we couldnt figure out what it was. well we ended up going threw the top half of the motor and didnt find anything. pulled the pan off and sure enough one of the rods was black. one of the bearings spun and welded itself to the crank but the thing didnt knock at all

 

+1 on the alternator my alternator would make a terrible whine that you could hear clearly inside. Got lucky and found one out of an astro van at the local J/Y that was brand new for 20 bucks and no more whine.