Serious KR - False or not

[BoyWonder]

I'm getting some serious KR showing on my SM
Reading in the 10s thru 15 degrees retard

Now
I know they say its pretty darned difficult to hear knock with the human ear over all the tire screeching and engine noise but I really don't hear any

It's so nice n cool here it Atlanta (when it's not raining latey) that it makes the car almost dangerous to drive - or drive in a straight line

But this KR has me terribly concerned and slightly peeved that I could be making so much more power
I always like Steve's opinion that no amount of KR is acceptable but I could certainly live with a couple if I had to
But c'mon - 15 degrees ?

So
I've seen the check list for hunting false knock
But short of tearing the car down to the frame, I'm trying to figure a plan for my course of action

1 - To determine if its real or false
2 - if it's false - what is the simplest executed plan to hunt it down

FYI
Lots of performance uogrades but the short block I beleive is stock
Cam sensor or tensioner (in that neighborhood) is unruly and making noise on cold start ups but quiets down after warm up
Sorta

Typical big down pipe that is close to everything
No torque strap as I holding off for an RJC torque plate

No knock gauge as I haven't pulled that trigger yet
Which knock gauge is the most popular?
Would be great if it could not clash with my Phanton II gauges but whatever

And I know I need a new cat hanger - pretty badly ( I would be embarrassed to say what is there right now) but I didn't do it
What I really need is a new shiny duel exhaust without the cat but that's for another time

So what I'm doing is sitting here trying to figure out my next move so I can see what this car is really capable of without KR in this nice 30 degree air
And without blowing a thousand bucks chasing ghosts

But I gotta get rid of the KR that's for sure since if it was real, it scares me
But I'm skeptical

Car is running too well and not clanging and banging all over the place
And all the SM numbers are right on the money so I feel good about the basic operation of the motor

Since it was easy- I did check the FPR pressure setting as Steve mentions a high pressure could cause squirrelly SM or knock anomalies - is 43 without vacuum maybe 42

Where to start?

 

[karst#9]

You can start by telling us your combo and some sm numbers

 

[BoyWonder]

Yes you're right

My post was sketchy on details. My bad.

Bweavy (who knows my WE4 pretty well) has me starting by looking at motor mounts (especially Driver's side) and then looking underneath for downpipe / exhaust contact on frame.

Which makes good sense.
So as soon as I swallow one more cup of coffee, I'm going to start hunting for engine movement.
He's pretty convinced it's all false KR due to something rubbing or rattling.


What he's more puzzled by is the unruly noise coming from either the tensioner or Cam Sensor that seems to quiet down after warming up for a while.
That doesn't jibe with him, since neither are oil temp dependant.
We don't know if my bottom end ever had rebuld done that could be noisy on cold start.
But to me- the noise is external and on the front end area around those two items I mentioned.

Another puzzle to be solved as well.

 

[Pronto]

You could try a cold start without the belt on to see if it's the tensioner.

 

[Grunk]

Checking the FP at idle does not really tell you much. You need to check the FP when under boost. If this is false knock you would get it under 1/2 or 3/4 throttle and even 5-10 lbs of boost. If you are seeing the problem at 15lbs of boost then your FP should go from 43 to 58 or so. You run 93 octane all the time right?

 

[BoyWonder]

You could try a cold start without the belt on to see if it's the tensioner.

Good idea on removing the belt.
"Forehead whack"

Yes, I run the highest they have - 93 or what have you.
Except for the one time I sleep walk and forget I'm not in my Dodge Ram and auto pilot press 87.
But only once.
No harm, no "foul"

As far as the FP - yes, you're right.
I have yet to rig up my in-cabin FP Gauge, but NEED to buy a temporary wiper mount unit.
I just threw that 43 at idle / no vacuum thing out there as a red herring.

So many things - so little time.
Not to mention, it is winter and the darned money tree out back seems to have become a little bare.

 

[BoyWonder]

I'm going to investigate any donwpipe / etc rattling or rubbing before I get too carried away.

I just hated to see 15 degrees of KR.
Can only imagine how strong it would be without it.
And not to mention, how bad KR is - if it's real knock.

But I'm not hearing what is "knock".
Although, like I said, with all the tire screeching and wind up - it's tough.

 

[karst#9]

(Swiped from Chad Schwartz)


Start-up knock? Normal and usually caused by the starter engaging the flex plate. Usually sets off 1-3 lights.

Possible bad ECM or ESC module. Test with good working units.

Exhaust rattle – check the down pipe, tail pipes, and have engine tie down strap

Boost creep especially top of 1st gear on 1-2 shift.

Lean air/fuel mixture.

To low octane gas – bad pump gas – try some race gas

Too much timing in chip for fuel used. Try different chip.

Try cooler spark plugs – use only AC Delco (R43-TS or R42-TS)

Gap plugs to .035

Check torque converter bolts to make sure they are tight

Loose harmonic balancer. Make sure torqued to 200 ft/lb Is keyway secure?

Check internal engine noises like timing chains (roller), lifters/rockers, etc.

Damaged knock sensor

Check fuel pump pressure and volume

Proper torque on knock sensor – 14 ft/lb

Check Alternator voltage: 13.8 - 14.5v

Check computer power wire - they can break internally.

Trouble shoot the computer connector power wires and ground wires.

Swap coil pack, wires, plugs w/known good units.

Swap MAF with known good unit.

Check battery ground connection @ block (clean/inspect).

Check/change battery cables (both).

Are there MAF leaks in the inlet tube?

Are there vacuum leaks. Use carb cleaner or WD-40 & spray everything. Does the rpm change?

Disconnect the main injector harness - inspect, WD-40. Check for moisture in main connector.

Disconnect the coil-pack connector - inspect pins & spray w/WD-40.

Is the cat still installed? Is it good?

Have you performed a leak down check?

Do the rockers open/close? Do we have a wiped cam lobe?

Is the boost/vacuum steady @ idle?

Is the engine over revving? Should be 4,800-5,200 rpm

Carbon in cylinders? Clean with GM engine top cleaner

Inter-cooler dirty? Clean inside inter-cooler and fins

Oil in intake tract?

Check for exhaust leaks, cracked header

Battery good?

EGR valve in working order?

Check that no cables, wires, etc are touching the knock sensor

Blown head gasket? Compression test. Should be around 150.

Injectors flowing/working correctly?

Check vacuum line to fuel pressure regulator for cracks

 

[SCOOBY DOO]

If your FP is rising 1 for 1 with boost...and you're not seeing KR at WOT...then it's likely false.

 

[BoyWonder]

Hehe..
Yes - the "check everything" list but thank you.

Start-up knock? Normal and usually caused by the starter engaging the flex plate. Usually sets off 1-3 lights.

Possible bad ECM or ESC module. Test with good working units. - Umm- Don't have another one but I'm doubting it - that's really fishing

Exhaust rattle – check the down pipe, tail pipes, and have engine tie down strap - Yeah - that's my thought. torque Strap is a no-go - I just don't want to see any broken accessory brackets

Boost creep especially top of 1st gear on 1-2 shift. - What exactly is "boost creep"/

Lean air/fuel mixture. - Maybe - But my O2's and BL's look good, if not great. I have a wideband on my wish list

To low octane gas – bad pump gas – try some race gas - The "experts"say that Race Gas is not the answer.. Steve has a pretty intellectual write up about how mixtures and octane do not neccesarily solve knock issues

Too much timing in chip for fuel used. Try different chip. - Yeah - Bob Baily chip and i'm going to yank it and see what it says on its belly

Try cooler spark plugs – use only AC Delco (R43-TS or R42-TS) - That's me

Gap plugs to .035 - Again - that's me

Check torque converter bolts to make sure they are tight - Could, and will check just for fun.

Loose harmonic balancer. Make sure torqued to 200 ft/lb Is keyway secure? Same thing - will check

Check internal engine noises like timing chains (roller), lifters/rockers, etc. - That's a "catch-all"

Damaged knock sensor - How does anyone ever really know when a sensor is good or bad? Other than replacing with known, new, good one. That is a throw back to shade tree mechanics where we are jsut replacing electrical pieces until we find the cause. I wish there was better way to check the knock sensor, but infortunately, probing the signal lines to the ESC requires some real intrusmentation and even then, I'm not sure I could carry it while running to capture the frequency output. (From an Electrical Engineer)

Check fuel pump pressure and volume - On my listto get a temp; windsheild wiper mounted FP gauge
Volume is another story - I always wanted a flow gauge. But pressure is a function of flow, (per Steve's writeup and basic fluid dynamics) so I'm going with a FP for now.

Proper torque on knock sensor – 14 ft/lb - I laid my hands right on it while I had the coil pack off and didn't feel it. But I will when I get a new one to install

Check Alternator voltage: 13.8 - 14.5v - Yes; albeit on the low side of that range

Check computer power wire - they can break internally. - Check - as in how? How would one check 'computer wiring"

Trouble shoot the computer connector power wires and ground wires. - Gook - with electrical grease

Swap coil pack, wires, plugs w/known good units. - Ugghh.again - All of them? Darned! But I am going to get a coil pack and ignition module as a spare for future troubleshoooting.

Swap MAF with known good unit. - Yeah - since I have good MAFs just laying around.
Hell, having one good MAF is a joy

Check battery ground connection @ block (clean/inspect). - My electrical system, and grounds; is A+

Check/change battery cables (both). - Check - they lookgreat, with anti corrisive grease, recently cleaned. Change out? Again - sounds like shade tree ghost chasing.

Are there MAF leaks in the inlet tube? - Not in my MAF tube - since it is polished alum

Are there vacuum leaks. Use carb cleaner or WD-40 & spray everything. Does the rpm change? - Minimized vacuum system (NO EGR) with all new silicone lines. But I am curios about where we are spraying the carb cleaner..at all fittings etc? To see if it get sucked into the intake? Interesting thought.

Disconnect the main injector harness - inspect, WD-40. Check for moisture in main connector. - Done - recently - completely clean and lubed

Disconnect the coil-pack connector - inspect pins & spray w/WD-40. - I use Q-Tip w/ Dielectric Grease afte cleanng all connectors with a Q-Tip wetted with light degreaser

Is the cat still installed? Is it good? - Yeah - and define good..;-)

Have you performed a leak down check? - Oh heck no

Do the rockers open/close? Do we have a wiped cam lobe? - Yes - and no

Is the boost/vacuum steady @ idle? - I would love to see where others install an underhood vacuum gauge
I want one like my fuel rail mounted pressure gauge, mounted somewhere cleanly

Is the engine over revving? Should be 4,800-5,200 rpm - NOOOO

Carbon in cylinders? Clean with GM engine top cleaner - I will do that sometime

Inter-cooler dirty? Clean inside inter-cooler and fins - Cleaned, regularly

Oil in intake tract? - not any more than gets sucked in theru the PCV

Check for exhaust leaks, cracked header - Those are regular, but currently not an issue

Battery good? - Want a new AC Delco but it is ok for now.

EGR valve in working order? - New

Check that no cables, wires, etc are touching the knock sensor - None - But I'm going to look again

Blown head gasket? Compression test. Should be around 150. - Oh heck..don't jinx me

Injectors flowing/working correctly? - Suppose so

Check vacuum line to fuel pressure regulator for cracks - All new silicone lines - complete

 

[karst#9]

Are you running stock boost level, how much boost? I thought i had false knock but it turned out to be vacumn issues