I have engine knock
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
I have engine knock
I have a 01 a4 with a vararam,magnaflow exhaust,ported tb and a diablo predator canned tune.I always use shell or chevron premium yet at WOT I get an engine knock.Anyone know what might cause this, perhaps I need to richen the fuel mixture slightly?
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
How sure are you that is a knock and not detonation? They sound different.. Check your DIC codes and see if you have the knock sensor code stored in history.. Canned tunes add alot of timing.. Undo the tune and see if that cures it.. If it does, then it's in the tune.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
I am not near the vehicle right but perhaps it may be detonation.I have seafoamed the vehicle twice in the past 6 months so I don't really thinks its detonation.
The most accurate representation of the noise hear is marbles being shook in a cannister.
The most accurate representation of the noise hear is marbles being shook in a cannister.
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
How sure are you that is a knock and not detonation? They sound different.. Check your DIC codes and see if you have the knock sensor code stored in history.. Canned tunes add alot of timing.. Undo the tune and see if that cures it.. If it does, then it's in the tune.
Does that make sense?
Thats why its called a knock sensor fault code.
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
The marble sound your hearing does sound like it could be detonation, you may want to consider taking the car someplace that has a wideband so you can find out what the AFR is if your unsure about your tune.
Drifting
Joined: Apr 2007
Posts: 1,848
Likes: 1
From: Central Florida
A code for a knock sensor would indicate a bad knock sensor or wiring or other problem related to a knock sensor, if your engine is knocking and the knock sensor is doing its job then you will not get a fault code for a knock sensor.
Does that make sense?
Thats why its called a knock sensor fault code.
Does that make sense?
Thats why its called a knock sensor fault code.
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
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Advanced
Joined: May 2002
Posts: 76
Likes: 0
From: Laguna Niguel CA
I had the same problem, I went in to the modify setting mod in the predator and first reduced (retarded) the timing by 25% (about 1 degree) that reduced the detonation some, so then I went in and decreased the air fuel mixture (made it richer). I cannot remember the units it is in but I deceased it by one increment. Check the Predators manual for instructions on how to achieve what I just recommended. I have been told the performance program advances the timing 5 degrees and is designed for 93 octane. It worked for mine because all we get in CA. is 91.
Instructor
Joined: Feb 2003
Posts: 137
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From: North Las Vegas NV
I have a 2001 MN6 with a ported TB and a high flow intake and a/predator, and I couldn't get rid of the ping either. Do yourself a favor and get a tune. I had Chuck COW do mine and now it's perfect. A lot of vettes get ping w/a intake. my 2 cents.
Former Vendor
Joined: Nov 2005
Posts: 11,792
Likes: 255
From: Ossining New York
St. Jude Donor '07-'08-'09-'10-'12-'13-'14
Here's the deal.....
#1) Confirm the fuel ocatne. VERY IMPORTANT. Min 91 required...use 93 if available.
#2) Remove the tune.....consider selling on E-bay to highest bidder.
#2.5) If you're a dumb-*** (know it or not) skip step #3 and call me cause I don't wanna hear it if you blow up your car or your face, or garage for that matter.
#3) Remove the MAF sensor and clean it with MASS AIR FLOW SENSOR CLEANER (available at most autoparts stores) if you can't find it....Brake cleaner or starting fluid will do.
#4) After flashing a computer or removing battery power....always drive the car easy for 10 minutes varying the throttle without WOT driving or passing gear.
Let me know how this works.
Chuck CoW
Instructor
Joined: Nov 2006
Posts: 114
Likes: 0
From: Hollywood CA
if it sounds like marbles in a can rattling around i would say 90% of the time its detonation... you sure your not running to lean? i had the same problem on a 03 cobra i use to own. i got a tune, ran to lean and everytime under WOT sounded like little BB's in a tin can....
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
Alright I ended up increasing the fuel at WOT throughout the powerband by 1% and I have put it in WOT 2 times since then and have not heard an ounce of knock.I'll keep you guys updated but it looks lie my problems are solved.
Former Vendor
Joined: Nov 2005
Posts: 11,792
Likes: 255
From: Ossining New York
St. Jude Donor '07-'08-'09-'10-'12-'13-'14
The reason you have a problem is because.....
I'm 90% sure you need to clean the MAF as it is likely a dirty MAF wire causing the car to run lean....
For the mods you've done, there should be no problem with pinging....
Use good gas....CLEAN THE MAF....remove the tune....
Test it out...You'll be fine.
Chuck CoW
Thread Starter
Melting Slicks
Joined: May 2007
Posts: 2,113
Likes: 0
From: Houston TX
The reason you have a problem is because.....you're lean....By adding fuel, the ping goes away.......
I'm 90% sure you need to clean the MAF as it is likely a dirty MAF wire causing the car to run lean....
For the mods you've done, there should be no problem with pinging....
Use good gas....CLEAN THE MAF....remove the tune....
Test it out...You'll be fine.
Chuck CoW
I'm 90% sure you need to clean the MAF as it is likely a dirty MAF wire causing the car to run lean....
For the mods you've done, there should be no problem with pinging....
Use good gas....CLEAN THE MAF....remove the tune....
Test it out...You'll be fine.
Chuck CoW
I cleaned the MAF about a month ago because my fuel economy was horrendous.I also only use shell/chevron gas ONLY.
Why would you recommend removing the tune though?
Former Vendor
Joined: Nov 2005
Posts: 11,792
Likes: 255
From: Ossining New York
St. Jude Donor '07-'08-'09-'10-'12-'13-'14
hand helds.....
Point is that for your application and the mods you've made...no tuning should be necessary to avoid pinging.
Try cleaning it again....really good....or swap one with one of your vette buddies if possible.
As a last resort, put the stock throttle body back on as a test....They not good for much anyway....
THOUSANDS of Vararams can't be wrong.
Chuck CoW
Tech Contributor
Joined: Jan 2007
Posts: 19,465
Likes: 1,167
From: Dyer, IN
Because it sounds like you have induced an error. Detonation is a bad thing, and if you are running too lean, could lead to bad things if you keep running at wide open throttle.