p0324 knock sensor code

[jerryhipp]

my wife fueled today. 87 octane and 5 minutes later the truck starts knocking, hesitating and threw a p0324 code. it is a 15 yukon denali 6.2l with 96,000mi. i know we are supposed to use higher octane. but we've always ran 87 octane and never had a problem. i was thinking it is just bad gas. and i threw a bottle of octane booster and gas line antifreeze in the tank. any opinions would be appreciated.

 

[STORMIN08]

although you have had no issues in the past, i would not recommend anything lower than spec'd...detonation can do sever damage.

even our 17 5.3 pings once in a while when loaded down and trying to accelerate to pass traffic...it gets 89 minimum since i first heard it. 55K miles now and have not had it do it since i switched.

 

[jerryhipp]

i dropped it off at the dealer 2 hours ago. they started it and instantly said bent pushrod, maybe lifters or more. they will diagnose it tomorrow. i don't get how it just happened out of nowhere. so now im sitting here expecting a phone call tomorrow telling me it will cost me 5k+ to fix it. then i will sell it. this is my 3rd tahoe/yukon and they are getting less and less reliable and more and more expensive. it may be time to move on.

 

[OR VietVet]

I doubt it is what the dealer said. If you only got a code and just a slight knock noise, I would agree with @STORMIN08 that it is likely the fuel octane and you are the problem and not the platform, Tahoe/Yukon, itself. If it has the damage that the dealer says, that noise would be very loud and very constant. Ask for proof of what they say and pics if you have them do the work and I highly recommend getting a second opinion. If you have a bent pushrod and lifters problem you should also have a misfire code as well. Your existing code is specifically for a knock sensor problem and not a cylinder misfire.

 

[jerryhipp]

it wasn't a slight knock. it was pretty loud. it was bent pushrods and lifters. $4300 is the cost. but i atleast got a junkie little buick suv as a courtesy car while they repair mine. i called a few other local shops. price was similar. so i just told the dealer to do it. so it will get done quicker and i atleast get a loaner. hopefully this will be the last issue i have with this truck.

 

[OR VietVet]

The loudness of the noise would be key. Got no idea why it never set a misfire code though.

 

[swathdiver]

my wife fueled today. 87 octane and 5 minutes later the truck starts knocking, hesitating and threw a p0324 code. it is a 15 yukon denali 6.2l with 96,000mi. i know we are supposed to use higher octane. but we've always ran 87 octane and never had a problem.

i dropped it off at the dealer 2 hours ago. they started it and instantly said bent pushrod, maybe lifters or more. ...i don't get how it just happened out of nowhere.

...this is my 3rd tahoe/yukon and they are getting less and less reliable and more and more expensive. it may be time to move on.

Penny wise and pound foolish! You do not know how this started and happened so fast? Baloney, it started when you started using low octane fuel in your high performance engine that you knew requires high octane gas. And then when it finally broke because of your actions you blame GM?

Running that swill in your motor usually results in a cracked piston and or rings which can then take out the pushrods, lifters, crack the block, etc.

You'll feel a lot better about yourself when you take responsibility for your actions.

 

[OR VietVet]

Penny wise and pound foolish! You do not know how this started and happened so fast? Baloney, it started when you started using low octane fuel in your high performance engine that you knew requires high octane gas. And then when it finally broke because of your actions you blame GM?

Running that swill in your motor usually results in a cracked piston and or rings which can then take out the pushrods, lifters, crack the block, etc.

You'll feel a lot better about yourself when you take responsibility for your actions.

A more detailed chewing out of what I said in post #4. Rightfully so. You can't deviate from what GM says to do to take care of your rig and then blame GM. Your fault, not GM's. Hopefully you saved enough fuel money from running low octane to pay the $4300. I bet you did not.

 

[Tiredmechanic23]

Penny wise and pound foolish! You do not know how this started and happened so fast? Baloney, it started when you started using low octane fuel in your high performance engine that you knew requires high octane gas. And then when it finally broke because of your actions you blame GM?

Running that swill in your motor usually results in a cracked piston and or rings which can then take out the pushrods, lifters, crack the block, etc.

You'll feel a lot better about yourself when you take responsibility for your actions.

Agreed. If it states to use 91 or 93 thats what should have been used period. That is what the vehicle is factory built and tuned for. Anything less will cause detonation and pinging even if so minor you do not notice it. Overtime does damage and kills an engine. Was it even top tier 87 or quality fuel? Same thing happens if you have a vehicle that factory uses 87 and you get a custom tune for 93 and then run low grade. Its just bad. These engines are known for lifter failure and it may be due to the AFM but you are doing no favors with the 87. The money saved is not worth it.

 

[jerryhipp]

lol. it says 91 octane is recommended but 87 is acceptable. just like all my hemi rams over the years. the computer compensates for the difference. the only downfall in lower octane is miniscule mpg. less than the cost difference. if it doesn't knock on 87 octane, then it is fine. never had this problem with any of my prior hemis or gms. it was the afm period. to blame it on octane is a joke. but you believe what you want.