improved/filtering/damping/????knocksensor

bezerk

bezerk

New member
i'am experiencing some mayor knock,
and i'am becoming allitle bit fed up to run trough everything again,again,again, and again,
so i already romved the knocksensor next to the thermostat, made sure that no lines are hitting the belhousing, and still i get 18KR..

this is false knock, and it is only there at +3500RPM

Does annybody has some good ideas about upgrading the knocksensor to a brand/model that isn't so accurate, but accurate enoug to see real deto?

is there a way to monitior, (like i can hear the knock that causes my KS to go wild).

how save is it to eliminate the knocksensor and use a different kind of knockmonitoring/etc.

Thanks
 
T

truckins10

Member
If you moved the sensor and you still see knock its probably real. If youve tried everything and checked everything then I would suggest H20 injection. Ive been in your shoes, and replaced everything I thought was suspect, and still would see 4-6KR on a stock chip/engine truck running 94octane gas. I built my own alky injection system, and what do you know, I see 2 when I first hit the gas and by 2nd shift I see 0KR all through the run. This is running the ultimate with 18psi boost. Im waiting to go the the track to turn it up more. The point is I thought it was fake to because I did everything to eliminate KR, but turns out it was real.

Couple things to check...
1. vertify TDC
2. Obiously resent tune up, upgraded fuel pump, fuel filter, vaccum leaks
3. carbon build up?? we get some special intake cleaner in a bottle and suck it through any vac line you can find while reving the engine, and you should see the blue smoke come out even new cars tailpipes because of all the carbon.

4. IC working??
5. engine running hot, check for buildup of sludge by looking in rad
6. set timing to 0, possibly try 2-3 degrees retarded>??
7. burning any oil, does truck smoke at startup??
8. Have you tried differant brands of gas to rule that out
9. vertify FP is rising with boost??
10. FP drop test?? this will make sure no injectors are plugged or not opening completely


Thats all I can think of off the top of my head.
Good luck Fern Sy#477

4.
 
bezerk

bezerk

New member
well thanks for the info..

But evrything is new, brand new engine, new #50 lb injectors, new rad. cap. rotor. NGK tr5 plugs.
i'am only running 10psi of boost,
FP is raising up to 62 when i'am at wot,
O2 shows 950Mv at wot,
Intake temp is about 50 degrees, engine runs at 73 degrees with 160F thermostat.

i disconnected the KS, and i can't hear anny deto
 
M

Maverick87

Member
Make sure that the downpipe isnt rubbing!!! I say this because I fought with kr for the longest time and it was still there. I wraped the dp and the kr went away. I checked time and time again and didnt think it was rubbing.But with the wrap on there I can see where it was !
 
Stangbeater

Stangbeater

How bout it?
bezerk said:
well thanks for the info..

But evrything is new, brand new engine, new #50 lb injectors, new rad. cap. rotor. NGK tr5 plugs.
i'am only running 10psi of boost,
FP is raising up to 62 when i'am at wot,
O2 shows 950Mv at wot,
Intake temp is about 50 degrees, engine runs at 73 degrees with 160F thermostat.

i disconnected the KS, and i can't hear anny deto
Click to expand...

What chip? I know someone (Dameon Barnhart) that had the same exact problem. He tried everything, then drove 4.5 hours to have someone else look at it. Pulled out the Ultimate and reseated it and the KR was gone.

SOB Why didn't I thinks of that? I mean Why didn't he think of that?
 
turbodig

turbodig

Active member
Re: improved/filtering/damping/????knocksensor

bezerk said:
i'am experiencing some mayor knock,
and i'am becoming allitle bit fed up to run trough everything again,again,again, and again,
so i already romved the knocksensor next to the thermostat, made sure that no lines are hitting the belhousing, and still i get 18KR..

this is false knock, and it is only there at +3500RPM

Does annybody has some good ideas about upgrading the knocksensor to a brand/model that isn't so accurate, but accurate enoug to see real deto?

is there a way to monitior, (like i can hear the knock that causes my KS to go wild).
Click to expand...


Yep... hook the line from the knock sensor up to the input on a tape recorder... hit record while you drive.

(depending on how sensitive your tape recorder input is, you might have
to deaden the signal somewhat so it doesn't clip off)


how save is it to eliminate the knocksensor and use a different kind of knockmonitoring/etc.

Thanks
Click to expand...


The J&S boxes were ok... better than nothing.
I'm really surprised somebody hasn't come out with something more
advanced (with regard to an add-on knock detection box)... there's
a market for it.

One point I want to make, though... I've had quite a few trucks/datalogs where people didn't hear any knock (thought it was false). It turned out to be very real. You can usually tell from where it is in the data and what conditions surround the knock if it's something that might be real.


Later,

Dig
'91 Sy - 11.83@112 |20g + a 9/11 TC.
 
bezerk

bezerk

New member
thanks Ryan for hosting my datamaster file!
i have ordered an water/alky kit.....

when i have some time, i will reisnstall my ultimate.
 
bezerk

bezerk

New member
okay i have ordered me a Water/alky kit..
still, if i have 18KR, and the ECM wants to eliminate knock so it starts pulling back timing, after that i still see 18KR, so this normally is false knock aint it?
 
P

protosy

New member
just out of curiosity, have you read your plugs lately? you should be able to tell pretty easily if its real knock or not by looking at them.

chad
 
turbodig

turbodig

Active member
Sigo said:
http://www.maydaymahem.com/movedknock2.uni
Click to expand...

02mv seems to indicate that you're not severely lean.... tough to tell
without a full WOT pass through the gears. Your o2s seem to fall off
after an early peak, though.


One thing I do see... your WOT voltage is down to 12.7 in places. This
would indicate a bad (noisy) alternator, or a grounding issue.

The ground issue is probably more likely. Check the frame ground by
the battery, and the one behind the driver's side cylinder head. Gotta be
clean, and paint-free.

I have redundant grounds in places between the frame and the engine,
and the ECM and the frame.

As to whether it's real or not, I've never seen one with KR like that, that you couldn't hear.

I'd check grounds and connections. Also, try a different base MEMCAL.

Recording the knock sensor (on tape or laptop) might also give you some
clues as to what's causing it. Regular patterned sounds will indicate some-
thing mechanical...

Later,
Dig
 
bezerk

bezerk

New member
base feulpressure is 42, i've tried several things,

I will check the grounds behind the heads.
and also try another ECM with memcal

list of things i did today:
again checked all the lines..
lowerd my transmission/transfercase about 0.4 inch, (to close to the body).
installed new TR5 plugs (after 300 miles)
checked timing
and uh...
got frustrated... :-?
reinstalled my ultimate chip

and still i get the stupid KR, sometimes it isn't there, when it comes it's mostly starts in the 3th gear, (could be an indication for the voltage, cause it pulls longer in 3th gear?)..

when i easlily step on the gas, (not floor it) and try to reach the 10 PSI it doesn't knock, when i floor it, (pedal to the metal) the KS goes wild, and the truck beginns to stumble.

Thanks for the help so far, and i need more of it i geuss :lol:
 
bezerk

bezerk

New member
about the memcall, i only have 1 OEM, can i use an Hypertech chip? for the ultimate to piggy back up?
 
bezerk

bezerk

New member
bezerk said:
about the memcall, i only have 1 OEM, can i use an Hypertech chip? for the ultimate to piggy back up?
Click to expand...

okay nevermind that, the Hypertech is the same as the ultimate..
things i did:
advanced timing by 5, and dissadvanced it, nothing worked:

can it be that my dist. is bad, and it doesn't change the timing?
bad sparkplugwires?
sparkplugwire to close to the KS-wire?

it feels so fast..........
 
K

kwick6

Donating Member
bezerk said:
i'am only running 10psi of boost,
FP is raising up to 62 when i'am at wot
Click to expand...

bezerk said:
base feulpressure is 42
Click to expand...


Did you set your fuel pressure with the vac line disconnected?

If you did set your base to 42, then you would read somewhere near 32 with vac line attached at idle. I would expect you to see a FP of 52 with 10psi.
 
mattw

mattw

Active member
Do you see the knock when you rev the engine in nuetral and hit 3500 RPM? I had tried to use an actual chain as an engine tie down once and the rattling that it did showed up as false knock... I could rev the motor in nuetral and it would always start around 3k and max out the KR. I agree thats its probably false.. I doubt the alky inj will make any diff....


Good Luck...


-Matt
 
bezerk

bezerk

New member
i set the Feulpressure as you discribed, and feulpressure is indeed somewhere around 55 with 10 PSI of boost
i can easlily make 10 PSI of boost without knock, i just have to take it easy on the pedal, but when i floor it knock is all over the place...

Still, if my knock is real, how would it be caused?
sometimes even when i am on cruiosecontrol i can see my KR alert coming up and down, like an visual equalizer.

damn....
 
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