Hi guys, I need some help. Recently Ive been having noises coming from under the hood( metalic scraping) I got it checked out and the mechanic said i would need to replace the entire Timing chain and components, as well as the AC compressor. Putting this much money into my Cobalt is like pulling a rabbit out of a hat. Its hard to say if I really need these issues fixed since they are so expensive. Also I keep noticing that when I shift, the RPMS stay up high and dont drop normal. Its as if the throttle stays wide open for too long. Eventually I get a check light for a p0388. Clutch switch. The mechanic said it might need to be adjusted. I did that tons of times before the metalic scraping noises came about, and also put a new clutch switch in. I have to reset the code to make it drive normal; which takes the noise away for a while. After about 5 miles the code comes back and the noise comes back. Is all this indeed, because of the bad Timing chain or failing AC compressor? Any help is a pluss. Thanks.

 

when you say "when you shift" do you mean the clutch is disengaged and the rpm will stay high? or when you put it into gear, release the clutch, press the gas, and the rpm satys up?

theres a timing chain tensioner on the back side of the valve cover on the passenger side. maybe that went ka-poot.

 

FLASH, what you asked is, two similar scenarios , but i will answer. When I "depress" the clutch, the tachometer will stay at whatever RPM it is at, until i "release" the clutch, forcing the rpm to drop back down. Similar to holding the gas while depressing the clutch and then releasing the gas and clutch. Thats what it feels like at least. I checked into Throttle body issues and hose leaks. Nothing. Check engine light is p0833 clutch switch. I did everything i could with the switch right above the clutch. Unless there is a different switch that I a missing, or potentially something different all together. Now that my engine is making scraping metallic noises, I question if a timing chain is throwing the codes, or playing a part in the RPMS not dropping....

 

While it is important to fix a timing chain or belt problem like a tensioner part or pully, it is equally important for me to figure out the root cause of this p0833, loss of cruise, and idol hang up; as this problem persists, and arose before the noises came from the engine.