weird knock retard issue *fixed*

[bezerk]

i did some datalog runs, my Sy is far from tuned but here is the deal.

i make about 4 runs WOT 0-60mph. first 3 runs max of 2.8KR , so all of the sudden the last run made about 10KR. all the paramaters looked the same, same Wbo2 reading, same temps. altough it was pulling timing like a mofo.
is this again my worst case scenario or false knock??

 

[Robert Lone]

Re: weird knock retard issue

Re: weird knock retard issue

Excessif heat in the chamber and piston from the previous runs???

 

[bezerk]

Re: weird knock retard issue

Re: weird knock retard issue

Excessif heat in the chamber and piston from the previous runs???

my intake temps were the same. also o knock untill 14 psi, and the 4 th run peaking at 6psi?

 

[Don W.]

Re: weird knock retard issue

Re: weird knock retard issue

If the runs are back-to-back it still could be a heat soak issue. Anything from a speck of carbon in the cyls to the ground electrode on the plugs. :2cents: 4th run at 6psi w/knock?

 

[bezerk]

Re: weird knock retard issue

Re: weird knock retard issue

yes, first 3 runs at WOT for about 5 sec on 15psi. the last one it bgans to knock at 70% throttle at 6psi 10KR. heatsoak..wouldn't my engine temp be alot higher as well at mats?

 

[Don W.]

Re: weird knock retard issue

Re: weird knock retard issue

Not necessarily IMHO. Water temps would remain close, oil temps would be up. But I wonder if it's going lean for some reason? 6psi is pretty low for knock. Maybe it is false.

I know that when at the drags if I make it into the late rounds temps will be up and KR would increase because of, presumably, no cool down time between rounds.

What happens if you give it some time between runs?

 

[bezerk]

Re: weird knock retard issue

Re: weird knock retard issue

there was something like 40 sec between those pulls, not like i did a 1/4 mile either or do boost launches..

 

[bezerk]

Re: weird knock retard issue

Re: weird knock retard issue

i don't have plates on my truck yet, so it was illegal to drive, i will make some more runs on monday when i get vin numbers stamped into the chassis and driving on temp. plates.
also have a code 43. try swapping out the knocksensor tomorrow and see if that causes the problem

 

[bezerk]

Re: weird knock retard issue *fixed*

Fixed the problem, installed a other knocksensor and put it on the lower intake, made a switch between the stock KS and this one, so i could swap back easlily if this wasn't my problem.
well no more code 43, and only 2KR at 18psi!! wooho.

only bad thing is that somehow i lost my boost control, i thought my Ext. Wastegate had a 10 psi spring, since i had rock solid boost at the beginning, bot somehow i manage to get 18PSI.
another issue solved, time to work out the next one

 

[Don W.]

Re: weird knock retard issue *fixed*

FWIW that just confirms that a new knock sensor will be going in my build. Did you move yours because the orig is so darn hard to get to? Or some other reason?

 

[bezerk]

Re: weird knock retard issue *fixed*

well, i had some knock issues on my other truck as well. i still haven't figured that out yet, but i just took it of at the easiest spot to get there. i know i did get abour 4kr lower readings on that other spot, and it's also easier to get too.

 

[sharkbait]

Re: weird knock retard issue *fixed*

Fixed the problem, installed a other knocksensor and put it on the lower intake, made a switch between the stock KS and this one, so i could swap back easlily if this wasn't my problem.
well no more code 43, and only 2KR at 18psi!! wooho.

only bad thing is that somehow i lost my boost control, i thought my Ext. Wastegate had a 10 psi spring, since i had rock solid boost at the beginning, bot somehow i manage to get 18PSI.
another issue solved, time to work out the next one

Bezerk, you said you put it in the lower intake? ive never seen one on the intake manifold. do you have a pic? thanks

 

[i8av8]

Re: weird knock retard issue *fixed*

pics also, please.

 

[WyoSyclone]

Re: weird knock retard issue *fixed*

Fixed the problem, installed a other knocksensor and put it on the lower intake, made a switch between the stock KS and this one, so i could swap back easlily if this wasn't my problem.
well no more code 43, and only 2KR at 18psi!! wooho.

Just a thought, but did you happen to put the new sensor in the stock location so that you could get a true a/b comparison? I wonder if the relatively soft aluminum of the lower intake could be masking some of the knock?? :dunno:

 

[dgoodhue]

Re: weird knock retard issue *fixed*

Here is mine.

I actually have done back to back comparisons. The lower intake manifold desensitize the knock sensor. (I supose it also mean I get more knock) It really only delayed my knock by ~1 sec, I was getting a ton of knock at the top of first, it just came on the bottom of 2nd gear. If you have a noise torque converter it will get it away from that.

 

[i8av8]

Re: weird knock retard issue *fixed*

Here is mine.

I actually have done back to back comparisons. The lower intake manifold desensitize the knock sensor. (I supose it also mean I get more knock) It really only delayed my knock by ~1 sec, I was getting a ton of knock at the top of first, it just came on the bottom of 2nd gear. If you have a noise torque converter it will get it away from that.

ok, i see where you mounted it, but what happens to the 2 wire sensor(black/yellow) that WAS there. i think it might be a coolant sensor, not sure or is it just on my set-up?

 

[i8av8]

Re: weird knock retard issue *fixed*

hold up, after further evaluation i see it isn't IN the spot i thought it was in. just couldn't see it with the tensioner in the way.

 

[autoaddictions]

Re: weird knock retard issue *fixed*

new knock sensor. Part# ????? what did you put in.

 

[bezerk]

Re: weird knock retard issue *fixed*

i put it in that samse spot as in the above pic. as far as the part number. i took it of of my Ty that is parked in the garage.

 

[10secTy]

Re: weird knock retard issue *fixed*

The best way to test if it false is to use a race gas before and after test. You do not want to desensitize the knock sensor to much.

We usually change the torque spec from 14lbs to 12lbs on motors with roller rockers and forged pistons.

Nolan