Knock wont stop.

[Norcalrallyist]

Ive posted in the other forums but to no avail. I thought advanced tuners might be able to tackle this question. I log knock well over 40 counts under WOT in any gear. There is no audible lifter noise, ive replaced the knock sensor I always use premium,ive tuned and retuned and retuned, ive changed wires and plugs several times, ive checked the caps for leackage and there is not oder or visable signs of leakage. This problem has been going on for months and no one can give me an answer. Pleased advanced tuners help me. Sorry if this is not worthy of advanced forum but I had to try.

 

[kpt4321]

What have you done in terms of tuning?

Have you put a wideband on the car? Have you tried taking a bunch of timing out on the CAS?

 

[Tevenor]

Boost level and a list of mods please.

 

[BUCK]

BSE?

 

[GSXanimal]

Did you check for a boost leak or possible carbon build up?

 

[AL92]

I have done a lot of reading on the phantom knock thing.I have some off idle sometimes but not at wot.The wot high counts is likely real.Too much boost not enough fuel the usual although some say super rich will knock too.Get a wideband on the car and see whats up.

What boost are you running what fuel mods..give me some info.

Anyway their seems to be many solutions to the phantom knock thing.first find out if yours is real.Tune the car.Also try racegas or mix xlylene or toluene 30 per cent and try that.Check for big things rattling loudly..exhuast stuff on or near the engine.Clean engine with combutstion chamber cleaner.Some people change out lifters to 3 g ones and some have luck changing out their knock sensor to a new one.Some have zero luck with anything and wind up selling the car or going to engine management system.Other options although a bit dangerous are moving the knock sensor or desensitizing it thru various methods.

Give me details maybe can help you out.

 

[Norcalrallyist]

I have a 2.5" turbo back exhaust with a test pipe and a flowmaster 2 chamber junker at the end. No fuel mods no increase to boost. I have stock timing that i have checked countless times to make sure double triple sure it is correct. I have the stock boost level around 10-11lb at wot. I have around 21hg at idle. I have checked for vacume leaks and boost leaks and can find none. I have replaced the knock sensor with a brand new mitsu sensor which actually did lower the knock count but not much. I cant hear any obnoxious rattling or anything that sounds like lifter noise. Im using TMO logger on a laptop to log and everything looks fine except the knock and the negative timing created by the computer. Ive also tried running the timing really retarded to see if that would knock less and that doesnt help. I dont have a wideband in the car just boost gauge and logger. I am considering swaping the ecu out to see if that makes a difference.. Maybe changing the lifters.. I really just wanted to do some basic mods and up the boost to 14-15 something the stock fuel system could handle and I cant even do that Please Please tell me whats wrong with this trash. :thumbdown

 

[Norcalrallyist]

Heres a link to someo f the other things ive tried and not had any results http://www.dsmtuners.com/forums/showthread.php?t=112420

 

[pneumo]

You said you checked the capacitors, but do you know if the previous owner ever changed them? If they're still original they will be toast no matter what. If you're not sure, have them changed.

What are you're O2 readings at WOT?

 

[Norcalrallyist]

You said you checked the capacitors, but do you know if the previous owner ever changed them? If they're still original they will be toast no matter what. If you're not sure, have them changed.

What are you're O2 readings at WOT?

Im positive they were never changed. But there is no visual indication or odor could this cause problems? Its been a while since ive logged since I havent found a reason to but I remember them being within the values that where suggested to be correct by a faq I found on this site.

 

[Norcalrallyist]

I had forgoten about disabling the wastegate on the turbo and running the logger. That would definately eliminate any possiblity of mechanical noise causing knock correct? So I guess the problem lies with my tuning? Is there anything else I should consider because I am positive that I have the timing set to stock. Still need some more suggestions. I really want to solve this.

 

[AL92]

I read a lot on the phantom knock site.Some guys had luck with some things..the decarb mopar combustion cleaner,some had luck with a new knock sensor,some with new lifters.one guy had bad motor mount.You get only knock under boost.That seems to say its real also .I get sometimes 43 counts off idle and off boost.that must be phantom.

10 counts won't likely hurt power much.You can try some race gas and see if it goes away.
Or mix 30 per cent toluene or xylene with your gas if you can't find racegas.

These cars are very strange.Will likely go to eprom ecu with knock programming or go to aem ems and take care of it with that. The knock retard off idle drives me nuts.You are leaving the lights and it hits.

I did think got rid of it for a bit when took out pcv for straight thru and catch can but had coolant leak and thought the car was pouring oil out of the breather on catch can so went back to stock.Think will try that again.Some have luck with restore stuff but not sure I like that goop in my engine.I used it but not sure would again.

Yours is weird but again if I only had 10 I wouldn't worry about it much.You could be lean though and like some said fuel pump is maybe likely if the injectors and fuel filter are good.

 

[GSX JOE]

Norcal, I have the same problem you do and have been trying to figure this out as well. Im getting over 20 counts of knock at about 12psi, it really sucks, especially since I have so much into this car (16g, 660's, fmic, safc etc.). Have you tryed racegas? On pump gas I cant even run 12psi w/ out knock but on c16 i can run 23psi w/ no signs of knock at all. This problem has gotten so bad my compression is roughly 115psi across all cylinders.

Anyway I have replaced my ecu, injectors, checked base timing, and fuel pump. I have a new fuel filter sitting here waiting to go on but i doubt that will do anything. Have you tried that seafoam engine cleaner? I know my car has very bad carbon build up but im not sure if that would cause this problem (I still need to try this). Anyways good luck and let me know if you have any success.

 

[Norcalrallyist]

The most ive tried is 91octane with octane boost.

 

[GSX JOE]

I know this post is kinda old but Norcal did you ever try putting in race gas? Ever fix your knock problem? Im still trying to figure out this knock problem on my car(c16 is really expensive).

 

[Norcalrallyist]

no I never tired .

 

[dsm10sec]

Are you still having the problem??

 

[jesepes]

Did you ever disconnect the wastegate actuator from the flapper arm? This way you can run WOT and have no boost. This will help you verify if boost is causing your problem, or whether it's phantom or malfunction, or loose engine parts, etc. Good luck.
-Jesse

 

[MNGSX]

Water carefully fed thru a vaccum line will help clean the CC..

How is the engine.. Miles etc... Really loose bores and or loose con rod bearings could do it too...

 

[greycar]

Haltechs have no knock sensor