redbird92'

iTrader: (1)

To start off I thank everyone that takes the time to help me. I have a L03 TBI 5 liter w/ duals, headers, dual snorkel air breather, and upgraded hypertech coil, and EBL FLASH.
I have done several VE learns and am basicly set with that. I am using the stock Spark advance.

I am seeing knks when PE is invoked. Numbers underlined are knks seen in WUD of EBL. average peak counts

RPM MAP
1600 95 1 2 3
1800 80 1 1 1 85 1 1 1
2000 85 1 1 1 90 2 3 4 100 2 2 3
2200 90 2 3 10 100 2 2 1
2400 85 1 1 1 90 2 2 1 95 2 2 2 100 2 2 1
2800 85 1 1 1 95 1 1 1 100 2 3 5
3200 95 3 4 2 100 5 8 8
3600 95 2 2 1

I hope I haven't lost you with that. These numbers are from 2 WOT runs from a 20-40mph cruise.
I pulled 3 plugs and they just looked a tiny bit white NO signs of detonation on plugs.

What I am looking for is a walk through to fix this problem and to get rid of the knks. I am a first time tuner and would like a little guidance with the spark advance. It only does this when PE is invoked. I only have a narrow band o2 sensor.
PLEASE HELP------I work a lot but I will check everyday so please post advice PLEASE

RBob

iTrader: (1)

There are a couple of ways to approach this. With the plugs already checked for detonation and no signs (fly-turd specs), then you can do something to further eliminate it as being true knock.

Open the main SA table and highlight the 85 - 100 KPa, 1600 - 4800 RPM area. Then use the toolbox and decrease the timing by 4 degrees. I picked that value as it is half of the largest retard (3200, 100 KPa). Flash that into a bank and try it out.

If the knock goes away then it was true detonation. In this case slowly increase the values (can use the above log values as a guide) to get the power back but short of roughness or detonation.

If removing the 4 degrees doesn't make a change, I'd say false knock. Then the fun begins as to what is causing it. The headers & dual clearance to the chassis is a good start.

The other item is that you only have a NB O2 sensor. Make sure that the engine isn't leaning out.

RBob.

liquidh8

FWIW, I have been chasing false know since i installed the TBI, with or without the EBL. I had total timing down to 24 degree, with vortec heads, and still get very erradic counts. I have a flat tappet cam, full roller rockets, long tubes and flowmaster super 40's. I've tried so far 3 different esc modules and 2 knock sensors. I have it kinda low know with the current set-up, but still getting false knock.

Do like RBob said, make certian it isn't real, plug checks and the like. Then you have to just chase it down. Good luck man.

redbird92'

iTrader: (1)

I took the SA down by for just like RBob said and I got fewer knks but still some.

RPM MAP average peak counts
1800 95 1 1 1
2000 95 1 1 1
2200 100 1 1 2
2800 100 1 2 2
3200 100 1 2 9
3600 95 2 5 16 100 3 4 4
4000 95 5 8 4
4400 95 3 5 6

So is this false knock???? thanks everyone!!!

redbird92'

iTrader: (1)

does anybody think this is false knock???? I will check out the exhaust what should I be looking for????

Ronny

iTrader: (1)

why not drop timing further or leave as is for now and run a tank of 92 octane?

redbird92'

iTrader: (1)

definetly will try the 92 octane gas. If that doesn't work I will drop the timing some more.
I have a idea if it false knock it could be a worn timing chain does this sound like it will cause knks at WOT
Is there any chance I can limit the amount of Sparkretard with my ebl flash????

I will report back later if the octane helps and/or the timing drop.

thanks everyone

DM91RS

Every time I have driven mine this year with the WHATSUP display running I get knock counts even at times I know there should be little to no load.

redbird92'

iTrader: (1)

So i put better octane in and dropped some timing and it seems to be less and when I say less I mean less map areas about 5 it still says I have retard up to 5deg. It like picks up a knk in 2400rpm 95-100 map and keeps going to 3000. but if it doesn't knock every WOT run just sometimes now which is a big improvement. Like if it doesn't pick up that 2400rpm knk it won't knk in say 26-28-3000 areas I am going to look in messing with AE I have a hunch that it is letting it go LEAN??? Any thoughts on this theroy or should I drop some more timing so far I dropped 6 deg

thanks guys

RBob

iTrader: (1)

I too have seen this when running the latest ESC modules. It is more of a random knock report, no consistency in where the knock occurs. These would be such as the HKR (5.7l) and HKM (5.0l) modules. They are a 2-pole filter which are not as good as the older 4-pole ESC modules (BLM).

Note that at key-off knock will be reported at some point in the matrix (RPM/MAP). The reason is that the ESC module is powered down immediately upon key-off. While the ECM is still running.

RBob.

RBob

iTrader: (1)

With 6 degrees pulled and higher octane fuel I'd say that it is false knock. That is unless the timing was crazy high to begin with. Is the engine smooth? Roughness is a sign of too much timing. And can be so high that knock doesn't have time to develop, the engine just runs rough.

What may be causing the reduced knock counts is the lower power of the engine. With the timing pulled it won't make as much power. With this it is less likely to torque over and cause contact between engine attached parts and frame attached parts.

Knock counts can also be caused by a noisy accessory. Basically a bad bearing on the alt, tensioner, etc.

RBob.

redbird92'

iTrader: (1)

Thanks RBob I am too thinking it is false knock I can hear what I think is the timing chain at idle with hood open I can't hear it when a load is put on it I will give the exhaust a 2nd look at the exhaust am I just looking for areas in which it hits the frame and areas that may have a leak in the pipes??????
If it is the timing chain should I do the cam swap at the same time to kill two birds with 1 stone. Thanks Everyone I will report back this weekend if it was a exhaust problem.

DM91RS

After logging every day this week to and back from work [23 miles-17 of it hwy] I have noticed that the knock seems to come at times of [for lack of better words] slack in the drive train. When I give it gas it disappears.

BUT the real problem still is an idle at times that is still surging. At times rock solid at others up and down. I did notice after Learn VE that certain cells would lean out and that if I added fuel that the surge went away. Yeah I know about lean idle surge but why is the VEL taking the fuel out?

I still have alot to learn. I just wished gas was lower and I was building the 6.0 of my dreams............LOL

Later..........DM

DM91RS

I forgot to add earlier........

I may try one of Grumpy's [RIP] suggestions for this issue which is to add a 90 degree fitting between the knock sensor and the block..........

To act as a filter........

RBob

iTrader: (1)

That is interesting about the driveline slack and knock counts. I've found similar instances with 700R4 downshifts (pull the shifter back at medium throttle). There are things that can be done with a stick tranny that will cause a lot of counts. But we won't mention what that is

The ESC module is an interesting filter. They not only respond to a particular frequency and amplitude, but also to a rapid change in frequency. Such as a sudden new noise.

The VEL just follows the BLM (or WB if being used that way). So if the BLM is low then the VEL will remove fuel (lower the VE%). Try increasing the O2 window in the areas that are problematic. This will keep the BLM from dropping. Note that while 'in idle' there is a separate set of window values.

May need a 45 deg fitting. The clearance for the sensor with a 90 deg fitting may be tight.

RBob.

redbird92'

iTrader: (1)

I changed the SA back to the stock values. I pulled plugs again and am getting a white condition. Looks like it is lean. I changed VE values so it will run rich and I still pick up knock. So even tho I gave it more gas the ECM uses the value in which it was in last, below 128 is ignored and 128 and above(adding gas) is used as fueling for PE. So by me adding gas in VE doesn,t richen up PE because the ECM compensates to get it around 128 so if the 02 is being influenced by the smashed exhaust pipe a lean condition will keep occuring... ANY THOUGHTS ON THIS STATEMENT
Would a restricted, smashed up exhaust cause the NB 02 to read richer than it is actually is.
I found a leak in exhaust and repaired it and it didn't help-- saw some problems where header collecters are near fly wheel cover and otherside might be hitting oil pan when engine is revved pipe has clearance of 1/2in maybe before touching pan when idling.
I might try setting PE afr to 12.50 or 12.1 and see if it does it......


ANY THOUGHTS ANYBODY espicially the smashed exhaust theroy

DM91RS

Sorry for being such a tard...but which are these separate settings.

I tried to post an attachment of a screen shot but I sux at that too so I'll just leave it to be explained.

RBob

iTrader: (1)

For when in idle:

INT - Idle O2 window Terms

For when not in idle:

INT - Mean R/L
INT - Rich O2 (Upper)
INT - Lean O2 (Lower)

The other thing I thought of was the smoothing. It can change values to smooth out the table. I usually reduce the smoothing factor as the VE table takes shape.

RBob.

RBob

iTrader: (1)

I had to think about this. A NB O2 sensor shouldn't be affected by backpressure. The reason I believe this to be true is that on some vehicles GM placed the NB O2 sensor between the head & a turbo.

On the other hand, a WB O2 sensor is affected by exhaust pressure.

RBob.

redbird92'

iTrader: (1)

It has to be true knock I checked the plugs they look lean. I used stock SA and put AFR for PE to 12.5 then 12.3 then 12.1 then 12 When i did this and did WOT run with each the knocks got fewer as i got richer i even took 2 then 3 deg out at some loads and it all had its effects but good ones. I finally stopped with 12.1 with 3 deg retard and only got 3 areas with average of 2deg ret.
It actually put you back in the seat some.
I got the exhaust fixed and it had no effects so I am gonna mess with the SA and PE and use different combos to see if I can get the knock to go away

ANY THOUGHTS on this and am I doing any harm with PE being 12 AFR

DM91RS

Thanks a bunch. I will tinker with those settings in the AM.

One great thing about the EBL code are all the adjustments that you can do. BUT for a knuckle head like myself I just get lost in all the terms.......

RBob

iTrader: (1)

No problem running the PE AFR as low as 12.0:1. The power will be dropping off a little, but it won't hurt the engine.

What one does need to watch for is running rich with excess timing. Feels good but isn't good for the engine.

White plugs (even bone white) is normal for stock EFI engines. Look at the plugs for tiny little carbon specks on the porcelain. Can you get an in-focus closeup picture of a couple of the plugs (porcelain area)? I'm not convinced it is real knock.

RBob.

redbird92'

iTrader: (1)

I am noy able to get pictures of plugs due to broken Camera. I have been searching for spark plugs reading pics and the only picture that looks like my plugs is from thr Haynes Manual and it is the Too Hot picture looks very similar to my plugs. Little brown spot on porcelin whitish electrode arm and a little blackish around threads. I see a little black specs on one but I think it is from me sanding it down and got some of the black stuff from the thread area on it. I checked 2 other plugs and no specs at all I wish I had a working camera.
I did delete the EGR from the ECM and I read that if you do this less timing is required??????? Any thoughts on this.

I get the most knock areas when going 50mph and go WOT when I go WOT from 0mph I get 2 areas

Another thought should I limit PE knock retard to say 1 or 2 and try a couple of runs with stock PE AFR and Stock timing and check plugs after a couple of runs??? If it is real knk I would be able to see it on plugs after that right??

redbird92'

iTrader: (1)

Checked out some more false knk things. I used a hose to pin point noises. Alternator has little whining noise probably the bearing not very loud. I also hear ticking noise next to valve covers by intake area not very loud tho was hard to find. It just sounds like normal sounds of lifters and rods etc. Took oil cap off to see if ticking got louder and I found it made no change so maybe a CAM noise???

Wouldn't a alternator noise have to be awfully loud to get a knk reading?

I will have to check out the Exhaust again and use some paint and paint frame parts and do a run and check for any signs of contact.


Thanks Rbob I do not know what I would do without your help

TMO

redbird92'. Thanks for your post. I have been reading for months and I have just started tuning with the EBL. I am going slow. I too get knock in PE mode and your experiment was very helpful.

Once I get the VE tables looking good I am faced with the problem of whether to add fuel or reduce SA. Based on other posts it appears the temptation is to add fuel and maintain high spark, but that this is not the correct approach.

This week I hope to have a heated NB O2 and a WB O2 installed just before the cat. From the posts it seems the best approach is to tune with the NB before going to the WB. The thought is that going directly to the WB will result in chasing my tail. That is, using the NB will force me to think through the issues. Any thoughts?

At some point I have to address the fact that all fuel in Minnesota by law must have at least 10% ethanol. This means I should be tuning for a stoich value of less than 14.7. My concern is the NB may not be able to handle a lower stoich value. Therefore, my thought is to first tune with the NB, then tune with the WB, and then go back to tuning for a lower stoich. Again, any thoughts?

redbird92'

iTrader: (1)

Ok finally got the WB installed and found i am in the high 13 low 14 at WOT. I am using the stock injectors 55#. My Flash EBL is telling me that I have a overflow on ve at 2800 to 3000 RPM.

My ve tables are getting maxed at the 100kpa area with a 100 being there value. Knocks getting less and less as more gas is given.

Should I need bigger injectors or some more fuel pressure with the mods I have?????? It seems that the stock injectors are getting maxed out.

ANY THOUGHT NEED HELP PLEASE

DM91RS

Read this. https://www.thirdgen.org/forums/diy-...tml?highlight=

Thomas actually has a cam and intake change where as I believe you are stock in that area so it looks like you can get by with more fuel pressure. But you can also change injectors and run the lower pressure. It amounts to how you want to spend your money and do the work. Just remember with either you need a fuel pump up to the task. To start with if you have not yet make your regulator adjustable and see how much you can get out of that simple and cheap mod.

redbird92'

iTrader: (1)

I just got some 61# and installed them and I am running open Loop. Now Wot is 12.4-12.9 which i am happy with but my VE tables are still 99-100 maxed at 95kpa and 100kpa but it runs fine now and I only get a couple of knocks now. I am thinking about getting a 350 L05 and doing a rebuild on it. Thanks everyone who gave their 2 cents on my problems you guys are the best. If any other problems arise I will re open this thread.

thanks