I'm really hoping someone can lead me to the issue on my Monte. It's a 3.4 engine and I recently replaced all the spark plugs and spark lines. After I ran the car I got the P0171 code. Figured I might have knocked something lose but I cannot find anything. I cleaned the MAF sensor and PCV valve and the engine light stayed off for a few days. It's back this morning.

So I am getting a too lean in bank 1, and I also noticed that there is a small whine coming from the car when I accelerate in the lower gears. It was there before my fix, but very hard to notice. When I went to look for it while the car was running it sounded like it was coming from the middle bottom area of the car, but I could not pinpoint it at the time. The car is running much smoother, but in idle it can run smooth and then get a bit shaky. The shaky goes away if I throttle the car. If I run it past second gear the whine ceases and the car runs smooth any time it is moving.

I appreciate any help toward this matter. I'm pretty burned out on doing repairs, but not on this car. It's been the first issue I have had with it in a long time.

My current suspicion is a gasket or line pulling in extra air that needs to be replaced or patched, but I am not familiar with where all the lines are to check beyond the main intake.

--------------------------------------------------------
-EDIT-

I looked up what information I could and it was suggested that the whine I am hearing is my power steering fluid could be low.

The shaky could be from the system trying to balance out the gas/air mix after it had been reset.

I also saw it recommended that I clean the MAF again, and replace the air filter, as I may not have cleaned it well enough. I also should either smoke the system with the cigar and tube method or use carb spray, having a fire extinguisher handy.

I hope I am just looking at a number of small issues together.

 

It was much simpler than I had expected.

There were two ports on the very top of the 3.4 engine that appeared to be/have been sealed up with vacuum caps that were cracked and old enough to crumble into dust when I touched them. New caps were about 50 cents. Put them on and the engine is running fine.

I will note that the back line had no cap when I found it. I had found a line that could have been there that was also crumbly and had broken far down the line. I did not see where it ran to. I will investigate tonight.

I did see that my power steering was low and topped it off. The whine is still present but softer, and still only triggers on acceleration in first and second gear lining up with acceleration. No whine when idling.

If anyone sees this before I figure it out please put in your thoughts. I am suspecting the old and long ago damaged line could be a part of the noise, but I have only heard the noise recently.

 

I get the same whine, if it's acceleration not when you turn don't think it's all power steering

where are those caps?

 

It turned out to be a small crack in the radiator. I have since patched it. Seems to be good.

 

Have somewhat the same whinning noise I was told it was my supercharger only makes the. Sound when I'm in gear thought it was my transmission but mechanic said it was my supercharger did gen v swap so look at the radiator