cmholbert

Help! I just bought a 97 grand am. 73000 miles, it has oil in it, and the check engine light is not on. But, I hear a loud knocking noise coming from my engine. It only does it when it is warm, and gets quieter when I accelerate. When I turn my wheel the noise changes tune. I can feel a vibration when I touch the left side of the motor. I was thinking it could be my timing chain?? Question, if I had a problem with my motor, wouldn't the check engine light come on???

99silverGT

does the noise sound like it is coming from the timing cover? usually a timing belt will be a dead give away. if it changes when u turn the wheel that might suggest a suspension problem or broken motor mount. as far as the check engine light, it may or may not come on if something is wrong. my friend had a toyota corolla with 90k on it, never had trouble, never a check engine light, threw a rod at 60mph.

bw_654

i have a similar problem right now. from what i know it is a rod knock. inside the engine.

Flatrater

If you want to isloated which cylinder has the knock remove one plug wire listen to the noise, the noise will change when you pull the plug on that cylinder! I use a 12 volt test light to do this, you don't need to keep restarting the car! Don't run the engine too long like this 30 seconds per cylinder max or you will fry the cat convertor.

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stanleyb51

Have the some problem. (56000 miles) knocking on the cylinder next to timing chain. (Very bad) on low RPM oil light shows. Lately I have trouble starting. Some oil shows on the top of the engine, between spark plugs, but all the vales cover gaskets are dry. Nearest station quotes $375.00 for replacing the chain, but I'm not sure if this is going to solve the problem. Any one solved this problem? Please Help, Email. Thank You

montana19

Im having a similar problem my car is a 95 and it knocks when idling and going slow when i accelerate im trying to find out what is wrong with it

montana19

i forgot a part of my last post when I accelerate over 45 it stops making the knocking noise someone please help

stanleyb51

Exectly some problem. Let's hope, someone will reply with some solution.

Fortah

i had same problem with my 97 grand am gt with 3.1 v-6
in 3.1 they have what is called a composite camshaft, its basically
a tube that has a small hole going thru the center, now here is the kicker
the lobes are pressed onto this shaft and keyed, the keys wears out and the lobe gives some movement ( which happen to break my camshaft), i had it into the shop 15 times and no one could find this problem till finally the camshaft broke, i had knocking sounds, no Horsepower (unless i really got on it, then it wasnt all there)
just something to look for
My car only has 80,000 miles on it

stanleyb51

Thanks for writing. I have my car in the shop. They determine that the knock is inside the engine. The price for rebuild engine (Long Block) is about $1800.00 plus another $600.00 for swapping. This will probably exceed the value of the car. I'm taking my chances with junk yard engine with 61000 mi. and I will install it myself. After this the car will go for sale.
I'm very disappointed. I purchased my first car in 1974 it was Buick Electra. Since then my family went thru 9 cars (all GM), but this was my last GM car in my life. Replacing an engine after 53000 mi is a joke. My next car will be Japanese. My friend just pass 220000 mi in his Honda Accord (Alternator was the only major part that failed on his car) One other think, placing water pump inside timing chain compartment is another one of this GM engineering wonders. Good Bye GM.