Cant Figure Out the Knock

[WS6]

You are correct
.....and traction is a problem on the street

L.A. County in its infinite wisdom has not built another track anywhere near my house since the last very successful one was demolished to mine gravel, so I have to stick to playing on the street for a while.

Interesting? You're maxing out the MAF at 256 g/s ,climbing past 90mph at roughly 12 lbs of boost and at 5000 RPM's all at 2.0 TPS volts.

Maybe then it's a faulty MAF?

A great thread none the less!


...

 

[GNBeswick]

Havnt ruled that out completely, but I just figured it maxes because Im flowing alot of air.

So in light of being completely stumped and extremely frustrated with the knock issues I poured what little methanol I had left into my tank and set out for a run with alky on. Set the blue knob at 12:00 position (my razor's alky kit is old, 2004 and doesnt have numbers) and hit the test button to make sure alky flowed. Did two runs up a my "track", which is a hill but its nice and wide and the cops dont go around there too much. Stupid me did not log the first run, but from the way it felt Im sure it wasnt much different from the 2nd one I logged. So in the recorded run, I eased into boost to make sure alky was flowing, than slowly gave it more and more throttle until the end where I gave it more of a stab almost to full throttle.
Now in comparison to my other logs there's some definite similarities. Just like all the other ones, at around 10.4lbs of boost knock comes in and settles down by the time it hits 12lbs. Not audible or anything. Now, near the end of the run you will notice a 0.7 0.5 0.2 knock sequence. I heard one audible "tick" of knock when this occurred. This also happened on the previous run I did not log. One audible tick. This once again stumps me. Only 15 lbs of boost with alky and I get knock? Than it goes away? The only thing that I find slightly odd is when this knock comes in, the AF ratio drops from 11:5 to a low of 10:6. When it comes back up to the 11:5 range the knock goes away.
Both runs were silky smooth with no power loss, stumble, or anything of that sort.

I had been holding off on the alky for a long time because I felt it was a bandaid or crutch. That the car should be able to make 15lbs of boost without it, and I wanted to make sure the car was truly at its limit before I put alky in the equation. I do now wonder if 13-14lbs of boost is all the car can run on straight 91 octane. I consider the knock in the 10lb boost range most likely false since it shows up in every run in the same place and I can never hear it. So if I take that out of the "alky run", its knock free until 15lbs. Logically that means to me that the alky is suppressing some real knock along the way.

Now I am left to wonder why the blip of knock at 15lbs with alky? And should I risk turning the boost up a bit with alky to see what it does? I think I should be able to get much more than 2-3 lbs of boost over 91 octane limit with alky.

Here is the run, has a short log of the car idling as well.

 

[Pronto]

Maybe you should call Julio and see if the pump needs to be checked out? I know he's changed a few things about the pump since 04. My alky turns on at about 7lbs and the transition is very smooth and no knock beyond 24lbs. He probably could give you some input on your knock issue as well.

 

[meanchicken]

On Cali 91 octane, it has also been my personal experience that 13-14lbs of boost is the best you can do without alky and not have KR.

Before my Alky install, I tried both 91 octane and then 50/50 mix 91 octane/100 octane.

With ony 91, I was getting KR and audible knock at 15lbs. With the 50/50 I would get absolultey no KR.

Lou C. would tell you the same...

 

[Boost231]

i havent read all the posts but have you put straight race gas in the tank and tested to see if you still get knock? if so i would try that

 

[Pronto]

Is the chip a 91 Octain?

 

[GNBeswick]

On Cali 91 octane, it has also been my personal experience that 13-14lbs of boost is the best you can do without alky and not have KR.

Before my Alky install, I tried both 91 octane and then 50/50 mix 91 octane/100 octane.

With ony 91, I was getting KR and audible knock at 15lbs. With the 50/50 I would get absolultey no KR.

Lou C. would tell you the same...

How much boost can you run with alky? Im still wondering why I got some knock with alky on.

Chip is for 91 octane ya, but even if it wasnt, to my knowledge the only thing different in a 93 chip is the timing, which I can adjust.

I havnt put race gas in....and I would love to, if I could find some.

 

[meanchicken]

How much boost can you run with alky? Im still wondering why I got some knock with alky on.

Chip is for 91 octane ya, but even if it wasnt, to my knowledge the only thing different in a 93 chip is the timing, which I can adjust.

I haven't put race gas in....and I would love to, if I could find some.

I'm currently runnin' 20lbs with 0 knock and my O2's right at 800+/- a little.
I found 100 octane at a local Union 76. Some of them carry it...but not all. I'm not sure where to get race gas.

Have we covered what spark plugs you're running and how fresh they are?
If you have the wrong spark plugs that can cause you some KR and breaking up at WOT.

 

[GNBeswick]

Well my plugs are as new as my engine, there's pics on page 1 or 2 of this thread. They are UR5's....I went with them because of the amount of praise in this thread. Mine are gapped at .35.

This is one of the latest logs I did with alky. I think there might have been too much spraying because I felt a little hesitation....and if you watch the log, the MAF goes crazy.

 

[Boost231]

i wish i wasn't so busy i would come by and have a look with you, im in ontario. anyways you need to roll into the throttle more and faster. i know you have knock but your at 5400 rpms at half throttle. get in 3rd and slowly mat it and when you see knock back out of it. This way we can see what is happening alittle better prior to knock. Also i would really try straight c16 and see what happens. i also fell your pain. i got so pissed at mine i gave up went to a XFI and some how that fixed it

 

[Boost231]

o one other thing. whats with the super low timing. when i was trying to figure mine out i didnt even go that low. and one other thing that i tryed on mine was, dieconnect the wastegate from the flapper so you have no boost take it out and make a pass and see what happens. record the log and post it up. mine wouldnt knock when i did this.

 

[GNBeswick]

Well, to try something new I disabled the wideband control to see what the car does. Reviewing the logs, it looks like the AF doesnt jump as much. I also set the timing to the default level it was programmed for. Of course there's no reprieve from the knock, and the headache continues. Looking at all the runs though, the MAF goes totally crazy and fluctuates all over the place. Seems it only does this with the alky kit on. (All my previous logs were with it turned off) So Im wondering if its interfering with the translator like Ive heard about? Or is that a sign of the MAF being bad? In these 3 runs I did not feel any sputter, surge, or backfire. There's also the knock that comes in at 10-12lbs boost......it's in almost every single run, alky or no alky. It almost always goes away too.....what could possibly be causing it at that level? I've watched the alky light come on more than once at the 5lb boost level, and while I have no real way of knowing....Im pretty sure the pump is actually spraying alky. If I hit the test button at idle, it makes the engine stumble real bad. I couldnt even hit 17lbs of boost without it knocking like crazy and the alky spraying.....something is seriously wrong there. There should have been more than enough alky spraying to surpress the knock as the knob was at 3/4 on alky7.dat and all the way down on alky8.dat. This damn car just gets more and more frustrating the more I do to solve the knock.

Here's the latest logs

 

[Pronto]

Is there anyway to try a stock MAF without the translator?

 

[TurboBuRick]

I though I saw it posted earlier. Have you tried unhooking the wastgate arm (running no boost) and seeing if this still shows up?

Rick

 

[GNBeswick]

Found my old stock MAF and hooked it up for a run. No MAF flutter with the alky on, but still have wonderful lovable knock at only 14lbs of boost. I even eased into the throttle the entire time.....should be able to hit more boost that way. Only 14lbs is ridiculous.....guys can run that on straight 91 octane.

I cannot unhook the wastegate arm because I do not use a stock style wastegate. I use an external wastegate off the downpipe and a Turbonetics boost controller.

Here is the run

 

[Jerryl]

Found my old stock MAF and hooked it up for a run. No MAF flutter with the alky on, but still have wonderful lovable knock at only 14lbs of boost. I even eased into the throttle the entire time.....should be able to hit more boost that way. Only 14lbs is ridiculous.....guys can run that on straight 91 octane.

I cannot unhook the wastegate arm because I do not use a stock style wastegate. I use an external wastegate off the downpipe and a Turbonetics boost controller.

Here is the run

This is what "I" would do ........

Turn the alky off, and make a a few runs.
Watch when KR starts. You wan t to make sure it is "repeatable".

Go to the pump, and add E-85, about 33% of total volume.
Make a few more runs, without making any changes.
Your 6.0 will track .........

If that helps the KR, you have narrowed it down a bit more.

 

[Pronto]

Is there any Sunoco stations that sell the 100 octane ul gas near you? You could try that or before I ran alky I made my own 100 octane by mixing Xylene 1 to 3 with 93 gas and a cap of marvel mystery oil. Run the 91 down as far as you can then add the higher octane stuff and see what happens. As far as the fluttering then it seems the translator may be getting messed up by the alky pump?

 

[ALVAROG1983]

Reply

LOL! If your bearings were that bad to be setting off the knock sensor, you would have no oil pressure and a rod knock at idle.

X2

 

[ALVAROG1983]

Help

o one other thing. whats with the super low timing. when i was trying to figure mine out i didnt even go that low. and one other thing that i tryed on mine was, dieconnect the wastegate from the flapper so you have no boost take it out and make a pass and see what happens. record the log and post it up. mine wouldnt knock when i did this.

IN THAT CASE YOUR IN INTARIO NOT TO FAR FROM ME ABOUT HALF AN HOUR AWAY, WHEN YOU GET SOME FREE TIME I WOULD LOVE FOR YOU TO HELP ME OUT ON MY XFI SYSTEM AM A NOVICE IM ABOUT TO TAKE IT BACK OUT AND RUN A STOCK ECM THAT IS HOW BAD I NEED I HAND.

AL

 

[meanchicken]

X2

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