i am new to working on my car so i need some help.

here is the background:

the cars engine light turned on and was running sluggish since its been hot, just thought i needed an oil change. it was really hot the other day and i was in the car for a few hours with the ac at full blast.
the first problem was the ac would blow out hot when the rpms got high but would get cold again when the rpms dropped. then the next problem was when the rpms got high, the whole car power would drop severely and i would have to shut off the ac completely. then the last problem was when i turned the ac back on the car started shaking and sputtering and made this high pitched screeching sound like a belt was off or something.
i immediately seafoamed the engine; crankshaft, vacuum lines, etc; since i first thought the oil was all mucked up and it needed to be cleaned. the engines performance greatly improved and is running a lot better but still doesn’t feel like 100% when i test drove it after the treatment.
of course when i turned on the ac though, the engine did the same thing: shaking sputtering and screeching.

here are my questions:
1. what could this be: belt, compressor, im so new at this, im just guessing
2. can the ac be flushed to take care of problem? can compressor be flushed and new oil added
3. my engine just got replaced at the beginning of the year so since i have a warranty, this should be covered with the new engine, right?

i cant afford more money at the mechanics so i needed some advice before i have to take the car in.

thank you so much to anyone who reads this.

 

Is it an orig compressor?

I am wondering if the compressor is going bad, signs of noise it can be bad. Esp if it happens with the AC on, plus you said it is blowing hot.

 

bad compressor

 

Check whether the condenser fan runs when the A/C turns on.

And pull the CEL codes.

 

old compressor? I thought the ac was replaced when you have an engine replacement? if so, then no, the new engine had 30,000 miles on it when installed, probably 35,000 now.

to be honest, i am afraid to turn the ac on since its making the car jump. am i going to create more damage if i turn the ac on? where do i look for the condensor fan?

i am very appreciative of all your advice and quick response!

 

Not the case all components are just taken off old engine and put back on new one, unless you got a junk yard engine with some components still on it.

 

It's a bad assumption to believe that the compressor was replaced when the engine was.

You can safely test the condenser fan (driver's side) by unplugging the connector for the compressor clutch.

 

ok, i did not know that. the engine was replaced by my mechanic who purchased it used, but dont know from where or if components were on it or not. after the replacement, the ac didnt work so we took it back and he charged it with freon but did not explain why it was like that. could it have been out of freon because it was removed from the old and was emptied before putting on the new engine? i guess i could ask the mechanic.

anyways, are there others things i can do to troubleshoot the problem in efforts to fix myself so i dont have to take it to the mechanics. after an engine replacement, i am broke.

thank you so much!!!!!!

 

sounds like compressor is siezed. i would replace it

 

I would run the car, turn on the ac, look under the hood and look at the compressor and listen it is making noise? Noise from the compressor is not good, freon or not.

 

I know this thread is old.
I had multiple issues with my 2000 Civic LX a/c. It quit working one summer. One shop couldn't figure it out but luckily didn't charge me. One shop wanted $1200 after their "diagnosis" proved everything in the a/c system needed replacement. I took it to my mom's b/f who did Hondas for 30+ years but is retired. He said of course it would work after replacing all the parts on it. He found a leaky Schrader valve and the clutch gap was too large. Refilled it with dye and no more leaks. It worked for a few years then it leaked again (I had to swap the engine after the wife drove it with a leaking coolant hose and I left the a/c compressor hanging by the lines during the swap. I found the leaks thanks to the dye. I replaced the condenser, 1 insulated line, 1 aluminum line, receiver/drier and I went for a R134a recharge. No leaks. I forgot to connect the condenser fan ground wire (I think, could have been another wire, one of the wires anyway) and the a/c engaged but overheated quickly in the shop due to the fan not working. It squealed like you described and we shut it off quickly. Ever since my a/c works but the compressor sounds like it's dying.
Hope this helps anyone who doesn't want to get screwed by a shop for replacing everything when it just needs a shim removed and a new valve. Plus ask for dye so you can trace a future leak and do the repairs yourself.