Spark knock on Hard Acceleration
Thread Starter
Racer
Joined: Mar 2003
Posts: 310
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Spark knock on Hard Acceleration
Looking for clues. I have a 2002 C5 coupe, 18000 miles. Have loud spark knock when I tromp it, it goes away after it develops RPM. I have tried different brands of gas- all 93 octane, changed plugs, check for codes and changed the fuel filter twice. Dealer says live with it. I took them the TSB about the knock sensor replacement- dealer said it did not apply to my VIN number and that it didn't sound that bad. Anyone have suggestions on what to check next? Thanks
Safety Car
Joined: Mar 2002
Posts: 4,928
Likes: 1
Cruise-In V Veteran
St. Jude Donor '09
Re: Spark knock on Hard Acceleration (boomer 33)
Most motors will knock under heavy load , low rpm, and high throttle angle ( heterogenous mixture, little swirl). Keep your Rs up. :cheers:
[Modified by binksZ06, 1:51 AM 3/20/2003]
[Modified by binksZ06, 1:51 AM 3/20/2003]
Thread Starter
Racer
Joined: Mar 2003
Posts: 310
Likes: 0
Re: Spark knock on Hard Acceleration (binksZ06)
Ok Mr. Binks, I will try and live with it. Just seems less than optimum and potentially damaging. 911 Carrera, 944 turbo, Yukon with 5.7, BMW 745, BMW 740I, BMW 533I - all didn't knock. Yet my Yukon with a 5.3 does unless I run 93 octane and to have this otherwise awesome C5 that knocks loudly no matter what I put in it seems mechanically backward. Thanks for your response. Do you think I ought to check the fuel pressure? (There I go again, sorry).
Thread Starter
Racer
Joined: Mar 2003
Posts: 310
Likes: 0
Re: Spark knock on Hard Acceleration (boomer 33)
Thanksfor kem and Bob, guided me to proceed with the TSB for this condition, I switched dealer and and have an appointmentt for next week to get my rear bank knock sensor replaced. And check the fuel pressre while thry are in there. Thanks to Ken and Bob. I wil let you know how it turns out. after that i am going to change the 2.73 fro 3.42 rears. Thnks, Cli :p:
Instructor
Joined: Nov 2002
Posts: 174
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From: West Columbia SC
Re: Spark knock on Hard Acceleration (boomer 33)
Is the car stock? My Granatelli MAF caused a lean condition which I straightened out with a Predator. I used to get detonation when maintaining about 3000 RPMS, and punched it.
Hope it works out for you.
:cheers:
