Malibu 2000 V6 Unstable the engine (vibration)

Hello, good day;

I have a 2000 Malibu with an SFI3100 engine.

Last night, I dropped some friends off, and on the way back, I had to accelerate to 70 km/h. The acceleration was rapid.

When I got home and slowed down, the car started shaking a lot and sounding like a clunker (like in the song).

This morning, I started the car, and it was shaking a lot, as if it were going to stall. The check engine light was flashing.
I drove to work, and the speed limit at work goes up to 90 km/h. During that time, I didn't feel the car vibrate, and in fact, at that speed, the car doesn't vibrate or make any noise; everything runs fine at that speed.
What I noticed is that when I let off the gas, the RPMs drop rapidly, whereas before they dropped slowly.

Reading on this forum, they mention that the problem is the IAC valve.

Is this possible?
Can I replace it myself?

The car has had its TPS, spark plug wires, spark plugs, air filter, oil, and oil filter replaced. The replacements were done less than a month ago.

Thank you very much!

I think it's the ignition coil! Check it and let me know what happens!

The mechanic already checked it. The first problem was a leaking injector, which was replaced yesterday.

The second, and more serious, problem is that one of the gaskets is damaged because water is leaking directly into the exhaust pipe, and all six cylinders aren't firing.

There's also internal engine wear.

The engine has failed and needs repair, and I have three options:

buy a rebuilt engine
, buy a used engine
, or repair my own engine.




Thanks for your reply, friend!