Cant Figure Out the Knock

[GNBeswick]

Ya, had knock before I started making adjustments.
Do you have the actual powerlogger program? You'll need that to view the files.

 

[GNBeswick]

Also, do you have a Power Plate? If so, are you sure it matches your plenum? #6 is defintately running richer than #5 by the looks of the pictures. I'm wondering if you have a Air dispersement problem in the intake?

Ya Ive got a powerplate, one for the stock plenum. I remember I checked it like 5 times before I put it on.

 

[Blown&Injected]

EGR has caused some knock issues for some.

Would be good to verify the coil, module, wires, and MAF, cam sensor, O2 sensors. What type of balancer? Some do not trip the crank sensor properly - mine was 4* off but the way you describe the knock it seems like more then that.

 

[Boost231]

i just looked at your logs. if i send you mine from when my motor was doing this they look Damn near the same. let me know what you find.

 

[meanchicken]

Fuel pressure is set at about 43psi line off and at 14lbs boost it only raised to about 51psi, or at least thats what it looked like to me.

Fuel Pressure at 14 lbs should be higher...should be at 57.
Are you sure your fuel pump is OK?

I just replaced my Walbro for similar issues. Pressure would jump up and then drop at boost leaving me lean and then KR would come in at 90-100MPH.

So I maxed out the fuel in my chip and max'd out the alky until I replaced the pump. Installed a Reds XP...problem solved...

You shouldn't force it into knock too frequently if you're sure it's real. Especially since you say you've shut off your Alky. You're gonna hurt that motor.

 

[GNBeswick]

Egr can cause knock even if the chip doesnt use it?
The module is brand new so I dont think its that, wires are russ meritt wires about 10 months old. Wideband is 3 months old too. Balancer is stock. I tried verifying the timing with a timing light after setting the ecm into diagnostic mode (15 degree timing) and it looked pretty good. Maybe 1-1.5 degrees retarded. Definately not advanced though.

 

[GNBeswick]

Fuel Pressure at 14 lbs should be higher...should be at 57.
Are you sure your fuel pump is OK?

I just replaced my Walbro for similar issues. Pressure would jump up and then drop at boost leaving me lean and then KR would come in at 90-100MPH.

So I maxed out the fuel in my chip and max'd out the alky until I replaced the pump. Installed a Reds XP...problem solved...

You shouldn't force it into knock too frequently if you're sure it's real. Especially since you say you've shut off your Alky. You're gonna hurt that motor.

Ya I know the math doesnt come out right, thats why I've asked if its possible to have a fueling problem with correct AF ratio. At the times of those runs I was not sure the knock was real. I baby the car now.
Did you have a wideband 02 to sense the AF when you were having trouble? How old was your pump? Mine is probably almost 4 years old now. Got it from Racetronix.

 

[TurboBuRick]

The PL files work fine but for some reason I'm not seeing the wideband signal. I thought you had a wideband. At any rate the stock o2 is rich so it's doubtful you have a fueling issue. Watching those logs, the knock does not act like traditional detonation. Real knock starts low and will progress. The knock in your recordings spikes then looks like a rattle some cases. The plugs also would support this. No sign of detonation on them. I don't like the NGK brand. I would replace with autolite or ac delco and see how she acts.

Rick

(EDIT) I got the wideband signal now. Must of had it set wrong. You are running a lc1?

 

[Blown&Injected]

I think I read something about the valve not sealing properly and that presumably was causing some trouble but I do not know for sure - never had to deal with that type of problem - just tossing out some stuff that you may not have considered.

The AFR seems to suggest that the fuel is being delivered in adequate amounts for the air.

Was the cam installed straight up? Sure about the final CR of the engine? Were there any issues with the rebuild?

 

[GNBeswick]

I think I read something about the valve not sealing properly and that presumably was causing some trouble but I do not know for sure - never had to deal with that type of problem - just tossing out some stuff that you may not have considered.

The AFR seems to suggest that the fuel is being delivered in adequate amounts for the air.

Was the cam installed straight up? Sure about the final CR of the engine? Were there any issues with the rebuild?

Hmm....how do you even go about checking a valve problem like that?
What do you mean by installed straight up? I assembled the engine myself after all the machine work. I do not recall encountering any problems, everything in my sig was done when I had the engine rebuilt (except for the injectors, those came 3 months later). I did a compression check and my cylinders are at 150. I used RJC Bulletproof headgaskets. The ported heads I bought off a board member and was told they were milled, but not by how much. The block was not decked.


And yes, I am running an LC-1

 

[Blown&Injected]

If you have it disabled, I would just get a block off plate - they are cheap and easy. One of the few times cheap and easy also works.

Like I was saying, I have not dealt with EGR problems myself but I think one way that may offer some clues, is to try to lift the valve with your fingers while the engine is running. They say it is possible to get ones fingers behind the valve and move the diaphragm.

By straight up - I mean the cam was not advanced or retarded

 

[Pronto]

You can log your fuel pressure with the Powerlogger. You need a transducer. I would also verifiy the LC-1 is reading the same on a laptop hooked directly up to it and using Innovate's software.
From Turbo Tweak website: Basically, the chip works like my 5.6 chip, except there are more adjustable features. It also can read the wideband reading from the Powerlogger and do corrections. In the chip, you have three target A/F adjustments, mid boost (3-14psi), WOT 1/2 gear, WOT 3/4 gear. If you set an A/F of 11.5, it will try to maintain that as best it can based on info from your wideband. You have to make sure your wideband is working properly so you don't get false info (garbage in, garbage out as they say). The program can add up to 33% fuel, and subtract 10% fuel to maintain the A/F. You can adjust the base WOT fuel to keep the correction inside the "window". I limited the subtraction to 10% so it can't get too crazy pulling fuel if something wrong happens.

Your mid boost 3-14psi might need adjustment.

 

[GNBeswick]

Ah ok....I remember making sure the cam was at no change, used a degree wheel. I have hooked up a laptop directly to the LC1 and it reads the same as my powerlogger. I have also set the mid boost to a 10:7 ratio.

 

[TurboBuRick]

I'm thinking 10.7 afr is rich for a low boost low timing tune with no alky. 10.7 would be a good afr if the alky was on with 25 psi boost and 24 degrees timing. Keep in mind rich knock can occur too. Thinking more like 11.7 would be more appropriate for a low timing low boost tune with straight up 93oct.

Plugs look good over all but I would go get set of ac's or autolites and file those ngk's in the nearest waist can. :biggrin:

 

[GNBeswick]

The reason I tried richening it up was because of knock. One of those powerlogger runs shows an Af ratio of about 11:5 or so ( it was the first run I did) and I still had knock. Octane is only 91 too, because California hates cars.

 

[bmackinnon]

If you have it disabled, I would just get a block off plate - they are cheap and easy. One of the few times cheap and easy also works.

Like I was saying, I have not dealt with EGR problems myself but I think one way that may offer some clues, is to try to lift the valve with your fingers while the engine is running. They say it is possible to get ones fingers behind the valve and move the diaphragm.

Both statements true, and perhaps worth a check.... I also don't feel very comfortable with the fuel pressure 'math not adding up'.... been watching this thread with interest... keep at it.... you'll get it figured out.... I would be making a concerted effort to find out why 2+2 doesn't equal 4 in the fp dept.....

 

[GNBeswick]

With the EGR check, if the valve lifts is it bad? Or is it if it doesnt lift? Im working on verifying the fuel pressure again now. Gonna try what ijames suggested with a bike pump.

 

[bmackinnon]

With the EGR check, if the valve lifts is it bad? Or is it if it doesnt lift? Im working on verifying the fuel pressure again now. Gonna try what ijames suggested with a bike pump.

With the engine idling, when you push the plunger (be careful, don't burn your fingers!), the engine should stumble badly and probably die.... that would indicate that the egr is (at least mostly) sealing... I'm doubting it's an egr problem, but I guess it's something else to check.....

 

[GNBeswick]

Ok, im having a hell of a time trying to test the AFPR with a pump and gauge. I can not get the lines to seal.....and I cant even figure out where air is leaking out of. What Im asking I guess is, is there something that I can get somewhere that will work, or something that someone has made that I can replicate?

 

[bmackinnon]

Use an air compressor instead of the bicycle pump.... regulated down to your desired output psi.....